diff --git a/packages/google-cloud-billing-budgets/src/v1beta1/budget_service_client.ts b/packages/google-cloud-billing-budgets/src/v1beta1/budget_service_client.ts
index ee7eb733053..bdf84672c03 100644
--- a/packages/google-cloud-billing-budgets/src/v1beta1/budget_service_client.ts
+++ b/packages/google-cloud-billing-budgets/src/v1beta1/budget_service_client.ts
@@ -45,8 +45,13 @@ export class BudgetServiceClient {
   private _innerApiCalls: {[name: string]: Function};
   private _pathTemplates: {[name: string]: gax.PathTemplate};
   private _terminated = false;
+  private _opts: ClientOptions;
+  private _gaxModule: typeof gax | typeof gax.fallback;
+  private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
+  private _protos: {};
+  private _defaults: {[method: string]: gax.CallSettings};
   auth: gax.GoogleAuth;
-  budgetServiceStub: Promise<{[name: string]: Function}>;
+  budgetServiceStub?: Promise<{[name: string]: Function}>;
 
   /**
    * Construct an instance of BudgetServiceClient.
@@ -70,8 +75,6 @@ export class BudgetServiceClient {
    *     app is running in an environment which supports
    *     {@link https://developers.google.com/identity/protocols/application-default-credentials Application Default Credentials},
    *     your project ID will be detected automatically.
-   * @param {function} [options.promise] - Custom promise module to use instead
-   *     of native Promises.
    * @param {string} [options.apiEndpoint] - The domain name of the
    *     API remote host.
    */
@@ -101,25 +104,28 @@ export class BudgetServiceClient {
     // If we are in browser, we are already using fallback because of the
     // "browser" field in package.json.
     // But if we were explicitly requested to use fallback, let's do it now.
-    const gaxModule = !isBrowser && opts.fallback ? gax.fallback : gax;
+    this._gaxModule = !isBrowser && opts.fallback ? gax.fallback : gax;
 
     // Create a `gaxGrpc` object, with any grpc-specific options
     // sent to the client.
     opts.scopes = (this.constructor as typeof BudgetServiceClient).scopes;
-    const gaxGrpc = new gaxModule.GrpcClient(opts);
+    this._gaxGrpc = new this._gaxModule.GrpcClient(opts);
+
+    // Save options to use in initialize() method.
+    this._opts = opts;
 
     // Save the auth object to the client, for use by other methods.
-    this.auth = gaxGrpc.auth as gax.GoogleAuth;
+    this.auth = this._gaxGrpc.auth as gax.GoogleAuth;
 
     // Determine the client header string.
-    const clientHeader = [`gax/${gaxModule.version}`, `gapic/${version}`];
+    const clientHeader = [`gax/${this._gaxModule.version}`, `gapic/${version}`];
     if (typeof process !== 'undefined' && 'versions' in process) {
       clientHeader.push(`gl-node/${process.versions.node}`);
     } else {
-      clientHeader.push(`gl-web/${gaxModule.version}`);
+      clientHeader.push(`gl-web/${this._gaxModule.version}`);
     }
     if (!opts.fallback) {
-      clientHeader.push(`grpc/${gaxGrpc.grpcVersion}`);
+      clientHeader.push(`grpc/${this._gaxGrpc.grpcVersion}`);
     }
     if (opts.libName && opts.libVersion) {
       clientHeader.push(`${opts.libName}/${opts.libVersion}`);
@@ -135,7 +141,7 @@ export class BudgetServiceClient {
       'protos',
       'protos.json'
     );
-    const protos = gaxGrpc.loadProto(
+    this._protos = this._gaxGrpc.loadProto(
       opts.fallback ? require('../../protos/protos.json') : nodejsProtoPath
     );
 
@@ -143,7 +149,7 @@ export class BudgetServiceClient {
     // identifiers to uniquely identify resources within the API.
     // Create useful helper objects for these.
     this._pathTemplates = {
-      budgetPathTemplate: new gaxModule.PathTemplate(
+      budgetPathTemplate: new this._gaxModule.PathTemplate(
         'billingAccounts/{billing_account}/budgets/{budget}'
       ),
     };
@@ -152,7 +158,7 @@ export class BudgetServiceClient {
     // (e.g. 50 results at a time, with tokens to get subsequent
     // pages). Denote the keys used for pagination and results.
     this._descriptors.page = {
-      listBudgets: new gaxModule.PageDescriptor(
+      listBudgets: new this._gaxModule.PageDescriptor(
         'pageToken',
         'nextPageToken',
         'budgets'
@@ -160,7 +166,7 @@ export class BudgetServiceClient {
     };
 
     // Put together the default options sent with requests.
-    const defaults = gaxGrpc.constructSettings(
+    this._defaults = this._gaxGrpc.constructSettings(
       'google.cloud.billing.budgets.v1beta1.BudgetService',
       gapicConfig as gax.ClientConfig,
       opts.clientConfig || {},
@@ -171,17 +177,36 @@ export class BudgetServiceClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this._innerApiCalls = {};
+  }
+
+  /**
+   * Initialize the client.
+   * Performs asynchronous operations (such as authentication) and prepares the client.
+   * This function will be called automatically when any class method is called for the
+   * first time, but if you need to initialize it before calling an actual method,
+   * feel free to call initialize() directly.
+   *
+   * You can await on this method if you want to make sure the client is initialized.
+   *
+   * @returns {Promise} A promise that resolves to an authenticated service stub.
+   */
+  initialize() {
+    // If the client stub promise is already initialized, return immediately.
+    if (this.budgetServiceStub) {
+      return this.budgetServiceStub;
+    }
 
     // Put together the "service stub" for
     // google.cloud.billing.budgets.v1beta1.BudgetService.
-    this.budgetServiceStub = gaxGrpc.createStub(
-      opts.fallback
-        ? (protos as protobuf.Root).lookupService(
+    this.budgetServiceStub = this._gaxGrpc.createStub(
+      this._opts.fallback
+        ? (this._protos as protobuf.Root).lookupService(
             'google.cloud.billing.budgets.v1beta1.BudgetService'
           )
         : // tslint:disable-next-line no-any
-          (protos as any).google.cloud.billing.budgets.v1beta1.BudgetService,
-      opts
+          (this._protos as any).google.cloud.billing.budgets.v1beta1
+            .BudgetService,
+      this._opts
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides
@@ -207,9 +232,9 @@ export class BudgetServiceClient {
         }
       );
 
-      const apiCall = gaxModule.createApiCall(
+      const apiCall = this._gaxModule.createApiCall(
         innerCallPromise,
-        defaults[methodName],
+        this._defaults[methodName],
         this._descriptors.page[methodName] ||
           this._descriptors.stream[methodName] ||
           this._descriptors.longrunning[methodName]
@@ -223,6 +248,8 @@ export class BudgetServiceClient {
         return apiCall(argument, callOptions, callback);
       };
     }
+
+    return this.budgetServiceStub;
   }
 
   /**
@@ -358,6 +385,7 @@ export class BudgetServiceClient {
     ] = gax.routingHeader.fromParams({
       parent: request.parent || '',
     });
+    this.initialize();
     return this._innerApiCalls.createBudget(request, options, callback);
   }
   updateBudget(
@@ -446,6 +474,7 @@ export class BudgetServiceClient {
     ] = gax.routingHeader.fromParams({
       'budget.name': request.budget!.name || '',
     });
+    this.initialize();
     return this._innerApiCalls.updateBudget(request, options, callback);
   }
   getBudget(
@@ -527,6 +556,7 @@ export class BudgetServiceClient {
     ] = gax.routingHeader.fromParams({
       name: request.name || '',
     });
+    this.initialize();
     return this._innerApiCalls.getBudget(request, options, callback);
   }
   deleteBudget(
@@ -608,6 +638,7 @@ export class BudgetServiceClient {
     ] = gax.routingHeader.fromParams({
       name: request.name || '',
     });
+    this.initialize();
     return this._innerApiCalls.deleteBudget(request, options, callback);
   }
 
@@ -700,6 +731,7 @@ export class BudgetServiceClient {
     ] = gax.routingHeader.fromParams({
       parent: request.parent || '',
     });
+    this.initialize();
     return this._innerApiCalls.listBudgets(request, options, callback);
   }
 
@@ -747,6 +779,7 @@ export class BudgetServiceClient {
       parent: request.parent || '',
     });
     const callSettings = new gax.CallSettings(options);
+    this.initialize();
     return this._descriptors.page.listBudgets.createStream(
       this._innerApiCalls.listBudgets as gax.GaxCall,
       request,
@@ -800,8 +833,9 @@ export class BudgetServiceClient {
    * The client will no longer be usable and all future behavior is undefined.
    */
   close(): Promise<void> {
+    this.initialize();
     if (!this._terminated) {
-      return this.budgetServiceStub.then(stub => {
+      return this.budgetServiceStub!.then(stub => {
         this._terminated = true;
         stub.close();
       });
diff --git a/packages/google-cloud-billing-budgets/synth.metadata b/packages/google-cloud-billing-budgets/synth.metadata
index 9f5bd7584c2..19123a93f4d 100644
--- a/packages/google-cloud-billing-budgets/synth.metadata
+++ b/packages/google-cloud-billing-budgets/synth.metadata
@@ -1,27 +1,13 @@
 {
-  "updateTime": "2020-02-14T12:14:16.238631Z",
+  "updateTime": "2020-03-05T23:02:52.309956Z",
   "sources": [
-    {
-      "git": {
-        "name": ".",
-        "remote": "https://github.com/googleapis/nodejs-billing-budgets.git",
-        "sha": "d4584c8c252f361b6e1505b1545183f66dc6abaa"
-      }
-    },
-    {
-      "git": {
-        "name": "synthtool",
-        "remote": "rpc://devrel/cloud/libraries/tools/autosynth",
-        "sha": "dd7cd93888cbeb1d4c56a1ca814491c7813160e8"
-      }
-    },
     {
       "git": {
         "name": "googleapis",
         "remote": "https://github.com/googleapis/googleapis.git",
-        "sha": "5169f46d9f792e2934d9fa25c36d0515b4fd0024",
-        "internalRef": "295026522",
-        "log": "5169f46d9f792e2934d9fa25c36d0515b4fd0024\nAdded cloud asset api v1p4beta1.\n\nPiperOrigin-RevId: 295026522\n\n56b55aa8818cd0a532a7d779f6ef337ba809ccbd\nFix: Resource annotations for CreateTimeSeriesRequest and ListTimeSeriesRequest should refer to valid resources. TimeSeries is not a named resource.\n\nPiperOrigin-RevId: 294931650\n\n"
+        "sha": "f0b581b5bdf803e45201ecdb3688b60e381628a8",
+        "internalRef": "299181282",
+        "log": "f0b581b5bdf803e45201ecdb3688b60e381628a8\nfix: recommendationengine/v1beta1 update some comments\n\nPiperOrigin-RevId: 299181282\n\n10e9a0a833dc85ff8f05b2c67ebe5ac785fe04ff\nbuild: add generated BUILD file for Routes Preferred API\n\nPiperOrigin-RevId: 299164808\n\n86738c956a8238d7c77f729be78b0ed887a6c913\npublish v1p1beta1: update with absolute address in comments\n\nPiperOrigin-RevId: 299152383\n\n73d9f2ad4591de45c2e1f352bc99d70cbd2a6d95\npublish v1: update with absolute address in comments\n\nPiperOrigin-RevId: 299147194\n\nd2158f24cb77b0b0ccfe68af784c6a628705e3c6\npublish v1beta2: update with absolute address in comments\n\nPiperOrigin-RevId: 299147086\n\n7fca61292c11b4cd5b352cee1a50bf88819dd63b\npublish v1p2beta1: update with absolute address in comments\n\nPiperOrigin-RevId: 299146903\n\n583b7321624736e2c490e328f4b1957335779295\npublish v1p3beta1: update with absolute address in comments\n\nPiperOrigin-RevId: 299146674\n\n638253bf86d1ce1c314108a089b7351440c2f0bf\nfix: add java_multiple_files option for automl text_sentiment.proto\n\nPiperOrigin-RevId: 298971070\n\n373d655703bf914fb8b0b1cc4071d772bac0e0d1\nUpdate Recs AI Beta public bazel file\n\nPiperOrigin-RevId: 298961623\n\ndcc5d00fc8a8d8b56f16194d7c682027b2c66a3b\nfix: add java_multiple_files option for automl classification.proto\n\nPiperOrigin-RevId: 298953301\n\na3f791827266f3496a6a5201d58adc4bb265c2a3\nchore: automl/v1 publish annotations and retry config\n\nPiperOrigin-RevId: 298942178\n\n01c681586d8d6dbd60155289b587aee678530bd9\nMark return_immediately in PullRequest deprecated.\n\nPiperOrigin-RevId: 298893281\n\nc9f5e9c4bfed54bbd09227e990e7bded5f90f31c\nRemove out of date documentation for predicate support on the Storage API\n\nPiperOrigin-RevId: 298883309\n\nfd5b3b8238d783b04692a113ffe07c0363f5de0f\ngenerate webrisk v1 proto\n\nPiperOrigin-RevId: 298847934\n\n541b1ded4abadcc38e8178680b0677f65594ea6f\nUpdate cloud asset api v1p4beta1.\n\nPiperOrigin-RevId: 298686266\n\nc0d171acecb4f5b0bfd2c4ca34fc54716574e300\n  Updated to include the Notification v1 API.\n\nPiperOrigin-RevId: 298652775\n\n2346a9186c0bff2c9cc439f2459d558068637e05\nAdd Service Directory v1beta1 protos and configs\n\nPiperOrigin-RevId: 298625638\n\na78ed801b82a5c6d9c5368e24b1412212e541bb7\nPublishing v3 protos and configs.\n\nPiperOrigin-RevId: 298607357\n\n4a180bfff8a21645b3a935c2756e8d6ab18a74e0\nautoml/v1beta1 publish proto updates\n\nPiperOrigin-RevId: 298484782\n\n6de6e938b7df1cd62396563a067334abeedb9676\nchore: use the latest gapic-generator and protoc-java-resource-name-plugin in Bazel workspace.\n\nPiperOrigin-RevId: 298474513\n\n244ab2b83a82076a1fa7be63b7e0671af73f5c02\nAdds service config definition for bigqueryreservation v1\n\nPiperOrigin-RevId: 298455048\n\n83c6f84035ee0f80eaa44d8b688a010461cc4080\nUpdate google/api/auth.proto to make AuthProvider to have JwtLocation\n\nPiperOrigin-RevId: 297918498\n\ne9e90a787703ec5d388902e2cb796aaed3a385b4\nDialogflow weekly v2/v2beta1 library update:\n  - adding get validation result\n  - adding field mask override control for output audio config\nImportant updates are also posted at:\nhttps://cloud.google.com/dialogflow/docs/release-notes\n\nPiperOrigin-RevId: 297671458\n\n1a2b05cc3541a5f7714529c665aecc3ea042c646\nAdding .yaml and .json config files.\n\nPiperOrigin-RevId: 297570622\n\ndfe1cf7be44dee31d78f78e485d8c95430981d6e\nPublish `QueryOptions` proto.\n\nIntroduced a `query_options` input in `ExecuteSqlRequest`.\n\nPiperOrigin-RevId: 297497710\n\ndafc905f71e5d46f500b41ed715aad585be062c3\npubsub: revert pull init_rpc_timeout & max_rpc_timeout back to 25 seconds and reset multiplier to 1.0\n\nPiperOrigin-RevId: 297486523\n\nf077632ba7fee588922d9e8717ee272039be126d\nfirestore: add update_transform\n\nPiperOrigin-RevId: 297405063\n\n0aba1900ffef672ec5f0da677cf590ee5686e13b\ncluster: use square brace for cross-reference\n\nPiperOrigin-RevId: 297204568\n\n5dac2da18f6325cbaed54603c43f0667ecd50247\nRestore retry params in gapic config because securitycenter has non-standard default retry params.\nRestore a few retry codes for some idempotent methods.\n\nPiperOrigin-RevId: 297196720\n\n1eb61455530252bba8b2c8d4bc9832960e5a56f6\npubsub: v1 replace IAM HTTP rules\n\nPiperOrigin-RevId: 297188590\n\n80b2d25f8d43d9d47024ff06ead7f7166548a7ba\nDialogflow weekly v2/v2beta1 library update:\n  - updates to mega agent api\n  - adding field mask override control for output audio config\nImportant updates are also posted at:\nhttps://cloud.google.com/dialogflow/docs/release-notes\n\nPiperOrigin-RevId: 297187629\n\n0b1876b35e98f560f9c9ca9797955f020238a092\nUse an older version of protoc-docs-plugin that is compatible with the specified gapic-generator and protobuf versions.\n\nprotoc-docs-plugin >=0.4.0 (see commit https://github.com/googleapis/protoc-docs-plugin/commit/979f03ede6678c487337f3d7e88bae58df5207af) is incompatible with protobuf 3.9.1.\n\nPiperOrigin-RevId: 296986742\n\n1e47e676cddbbd8d93f19ba0665af15b5532417e\nFix: Restore a method signature for UpdateCluster\n\nPiperOrigin-RevId: 296901854\n\n7f910bcc4fc4704947ccfd3ceed015d16b9e00c2\nUpdate Dataproc v1beta2 client.\n\nPiperOrigin-RevId: 296451205\n\nde287524405a3dce124d301634731584fc0432d7\nFix: Reinstate method signatures that had been missed off some RPCs\nFix: Correct resource types for two fields\n\nPiperOrigin-RevId: 296435091\n\ne5bc9566ae057fb4c92f8b7e047f1c8958235b53\nDeprecate the endpoint_uris field, as it is unused.\n\nPiperOrigin-RevId: 296357191\n\n8c12e2b4dca94e12bff9f538bdac29524ff7ef7a\nUpdate Dataproc v1 client.\n\nPiperOrigin-RevId: 296336662\n\n17567c4a1ef0a9b50faa87024d66f8acbb561089\nRemoving erroneous comment, a la https://github.com/googleapis/java-speech/pull/103\n\nPiperOrigin-RevId: 296332968\n\n3eaaaf8626ce5b0c0bc7eee05e143beffa373b01\nAdd BUILD.bazel for v1 secretmanager.googleapis.com\n\nPiperOrigin-RevId: 296274723\n\ne76149c3d992337f85eeb45643106aacae7ede82\nMove securitycenter v1 to use generate from annotations.\n\nPiperOrigin-RevId: 296266862\n\n203740c78ac69ee07c3bf6be7408048751f618f8\nAdd StackdriverLoggingConfig field to Cloud Tasks v2 API.\n\nPiperOrigin-RevId: 296256388\n\ne4117d5e9ed8bbca28da4a60a94947ca51cb2083\nCreate a Bazel BUILD file for the google.actions.type export.\n\nPiperOrigin-RevId: 296212567\n\na9639a0a9854fd6e1be08bba1ac3897f4f16cb2f\nAdd secretmanager.googleapis.com v1 protos\n\nPiperOrigin-RevId: 295983266\n\nce4f4c21d9dd2bfab18873a80449b9d9851efde8\nasset: v1p1beta1 remove SearchResources and SearchIamPolicies\n\nPiperOrigin-RevId: 295861722\n\ncb61d6c2d070b589980c779b68ffca617f789116\nasset: v1p1beta1 remove SearchResources and SearchIamPolicies\n\nPiperOrigin-RevId: 295855449\n\nab2685d8d3a0e191dc8aef83df36773c07cb3d06\nfix: Dataproc v1 - AutoscalingPolicy annotation\n\nThis adds the second resource name pattern to the\nAutoscalingPolicy resource.\n\nCommitter: @lukesneeringer\nPiperOrigin-RevId: 295738415\n\n8a1020bf6828f6e3c84c3014f2c51cb62b739140\nUpdate cloud asset api v1p4beta1.\n\nPiperOrigin-RevId: 295286165\n\n5cfa105206e77670369e4b2225597386aba32985\nAdd service control related proto build rule.\n\nPiperOrigin-RevId: 295262088\n\nee4dddf805072004ab19ac94df2ce669046eec26\nmonitoring v3: Add prefix \"https://cloud.google.com/\" into the link for global access\ncl 295167522, get ride of synth.py hacks\n\nPiperOrigin-RevId: 295238095\n\nd9835e922ea79eed8497db270d2f9f85099a519c\nUpdate some minor docs changes about user event proto\n\nPiperOrigin-RevId: 295185610\n\n5f311e416e69c170243de722023b22f3df89ec1c\nfix: use correct PHP package name in gapic configuration\n\nPiperOrigin-RevId: 295161330\n\n6cdd74dcdb071694da6a6b5a206e3a320b62dd11\npubsub: v1 add client config annotations and retry config\n\nPiperOrigin-RevId: 295158776\n\n"
       }
     },
     {
diff --git a/packages/google-cloud-billing-budgets/test/gapic-budget_service-v1beta1.ts b/packages/google-cloud-billing-budgets/test/gapic-budget_service-v1beta1.ts
index 55b9158ef72..20914411f8b 100644
--- a/packages/google-cloud-billing-budgets/test/gapic-budget_service-v1beta1.ts
+++ b/packages/google-cloud-billing-budgets/test/gapic-budget_service-v1beta1.ts
@@ -83,12 +83,30 @@ describe('v1beta1.BudgetServiceClient', () => {
     });
     assert(client);
   });
+  it('has initialize method and supports deferred initialization', async () => {
+    const client = new budgetserviceModule.v1beta1.BudgetServiceClient({
+      credentials: {client_email: 'bogus', private_key: 'bogus'},
+      projectId: 'bogus',
+    });
+    assert.strictEqual(client.budgetServiceStub, undefined);
+    await client.initialize();
+    assert(client.budgetServiceStub);
+  });
+  it('has close method', () => {
+    const client = new budgetserviceModule.v1beta1.BudgetServiceClient({
+      credentials: {client_email: 'bogus', private_key: 'bogus'},
+      projectId: 'bogus',
+    });
+    client.close();
+  });
   describe('createBudget', () => {
     it('invokes createBudget without error', done => {
       const client = new budgetserviceModule.v1beta1.BudgetServiceClient({
         credentials: {client_email: 'bogus', private_key: 'bogus'},
         projectId: 'bogus',
       });
+      // Initialize client before mocking
+      client.initialize();
       // Mock request
       const request: protosTypes.google.cloud.billing.budgets.v1beta1.ICreateBudgetRequest = {};
       request.parent = '';
@@ -112,6 +130,8 @@ describe('v1beta1.BudgetServiceClient', () => {
         credentials: {client_email: 'bogus', private_key: 'bogus'},
         projectId: 'bogus',
       });
+      // Initialize client before mocking
+      client.initialize();
       // Mock request
       const request: protosTypes.google.cloud.billing.budgets.v1beta1.ICreateBudgetRequest = {};
       request.parent = '';
@@ -137,6 +157,8 @@ describe('v1beta1.BudgetServiceClient', () => {
         credentials: {client_email: 'bogus', private_key: 'bogus'},
         projectId: 'bogus',
       });
+      // Initialize client before mocking
+      client.initialize();
       // Mock request
       const request: protosTypes.google.cloud.billing.budgets.v1beta1.IUpdateBudgetRequest = {};
       request.budget = {};
@@ -161,6 +183,8 @@ describe('v1beta1.BudgetServiceClient', () => {
         credentials: {client_email: 'bogus', private_key: 'bogus'},
         projectId: 'bogus',
       });
+      // Initialize client before mocking
+      client.initialize();
       // Mock request
       const request: protosTypes.google.cloud.billing.budgets.v1beta1.IUpdateBudgetRequest = {};
       request.budget = {};
@@ -187,6 +211,8 @@ describe('v1beta1.BudgetServiceClient', () => {
         credentials: {client_email: 'bogus', private_key: 'bogus'},
         projectId: 'bogus',
       });
+      // Initialize client before mocking
+      client.initialize();
       // Mock request
       const request: protosTypes.google.cloud.billing.budgets.v1beta1.IGetBudgetRequest = {};
       request.name = '';
@@ -210,6 +236,8 @@ describe('v1beta1.BudgetServiceClient', () => {
         credentials: {client_email: 'bogus', private_key: 'bogus'},
         projectId: 'bogus',
       });
+      // Initialize client before mocking
+      client.initialize();
       // Mock request
       const request: protosTypes.google.cloud.billing.budgets.v1beta1.IGetBudgetRequest = {};
       request.name = '';
@@ -235,6 +263,8 @@ describe('v1beta1.BudgetServiceClient', () => {
         credentials: {client_email: 'bogus', private_key: 'bogus'},
         projectId: 'bogus',
       });
+      // Initialize client before mocking
+      client.initialize();
       // Mock request
       const request: protosTypes.google.cloud.billing.budgets.v1beta1.IDeleteBudgetRequest = {};
       request.name = '';
@@ -258,6 +288,8 @@ describe('v1beta1.BudgetServiceClient', () => {
         credentials: {client_email: 'bogus', private_key: 'bogus'},
         projectId: 'bogus',
       });
+      // Initialize client before mocking
+      client.initialize();
       // Mock request
       const request: protosTypes.google.cloud.billing.budgets.v1beta1.IDeleteBudgetRequest = {};
       request.name = '';
@@ -283,6 +315,8 @@ describe('v1beta1.BudgetServiceClient', () => {
         credentials: {client_email: 'bogus', private_key: 'bogus'},
         projectId: 'bogus',
       });
+      // Initialize client before mocking
+      client.initialize();
       // Mock request
       const request: protosTypes.google.cloud.billing.budgets.v1beta1.IListBudgetsRequest = {};
       request.parent = '';
@@ -310,6 +344,8 @@ describe('v1beta1.BudgetServiceClient', () => {
         credentials: {client_email: 'bogus', private_key: 'bogus'},
         projectId: 'bogus',
       });
+      // Initialize client before mocking
+      client.initialize();
       // Mock request
       const request: protosTypes.google.cloud.billing.budgets.v1beta1.IListBudgetsRequest = {};
       request.parent = '';