diff --git a/src/transporters.ts b/src/transporters.ts
index 33dca5ff..0b4e2617 100644
--- a/src/transporters.ts
+++ b/src/transporters.ts
@@ -68,19 +68,9 @@ export class DefaultTransporter implements Transporter {
         ] = `${uaValue} ${DefaultTransporter.USER_AGENT}`;
       }
       // track google-auth-library-nodejs version:
-      const authVersion = `auth/${pkg.version}`;
-      if (
-        opts.headers['x-goog-api-client'] &&
-        !opts.headers['x-goog-api-client'].includes(authVersion)
-      ) {
-        opts.headers[
-          'x-goog-api-client'
-        ] = `${opts.headers['x-goog-api-client']} ${authVersion}`;
-      } else if (!opts.headers['x-goog-api-client']) {
+      if (!opts.headers['x-goog-api-client']) {
         const nodeVersion = process.version.replace(/^v/, '');
-        opts.headers[
-          'x-goog-api-client'
-        ] = `gl-node/${nodeVersion} ${authVersion}`;
+        opts.headers['x-goog-api-client'] = `gl-node/${nodeVersion}`;
       }
     }
     return opts;
diff --git a/test/test.transporters.ts b/test/test.transporters.ts
index 08410db4..97a72465 100644
--- a/test/test.transporters.ts
+++ b/test/test.transporters.ts
@@ -58,11 +58,7 @@ describe('transporters', () => {
     const opts = transporter.configure({
       url: '',
     });
-    assert(
-      /^gl-node\/[.-\w$]+ auth\/[.-\w$]+$/.test(
-        opts.headers!['x-goog-api-client']
-      )
-    );
+    assert(/^gl-node\/[.-\w$]+$/.test(opts.headers!['x-goog-api-client']));
   });
 
   it('should append to x-goog-api-client header if it exists', () => {
@@ -70,9 +66,7 @@ describe('transporters', () => {
       headers: {'x-goog-api-client': 'gdcl/1.0.0'},
       url: '',
     });
-    assert(
-      /^gdcl\/[.-\w$]+ auth\/[.-\w$]+$/.test(opts.headers!['x-goog-api-client'])
-    );
+    assert(/^gdcl\/[.-\w$]+$/.test(opts.headers!['x-goog-api-client']));
   });
 
   // see: https://github.com/googleapis/google-auth-library-nodejs/issues/819
@@ -84,9 +78,7 @@ describe('transporters', () => {
     let configuredOpts = transporter.configure(opts);
     configuredOpts = transporter.configure(opts);
     assert(
-      /^gdcl\/[.-\w$]+ auth\/[.-\w$]+$/.test(
-        configuredOpts.headers!['x-goog-api-client']
-      )
+      /^gdcl\/[.-\w$]+$/.test(configuredOpts.headers!['x-goog-api-client'])
     );
   });