diff --git a/examples/features/authentication/client/main.go b/examples/features/authentication/client/main.go
index 29b125d22ff..a189b4be8cf 100644
--- a/examples/features/authentication/client/main.go
+++ b/examples/features/authentication/client/main.go
@@ -50,7 +50,7 @@ func main() {
 	flag.Parse()
 
 	// Set up the credentials for the connection.
-	perRPC := oauth.TokenSource{oauth2.StaticTokenSource(fetchToken())}
+	perRPC := oauth.TokenSource{TokenSource: oauth2.StaticTokenSource(fetchToken())}
 	creds, err := credentials.NewClientTLSFromFile(data.Path("x509/ca_cert.pem"), "x.test.example.com")
 	if err != nil {
 		log.Fatalf("failed to load credentials: %v", err)
diff --git a/examples/features/interceptor/client/main.go b/examples/features/interceptor/client/main.go
index e8f19a12e52..0832e4861cd 100644
--- a/examples/features/interceptor/client/main.go
+++ b/examples/features/interceptor/client/main.go
@@ -56,7 +56,7 @@ func unaryInterceptor(ctx context.Context, method string, req, reply interface{}
 	}
 	if !credsConfigured {
 		opts = append(opts, grpc.PerRPCCredentials(oauth.TokenSource{
-			oauth2.StaticTokenSource(&oauth2.Token{AccessToken: fallbackToken}),
+			TokenSource: oauth2.StaticTokenSource(&oauth2.Token{AccessToken: fallbackToken}),
 		}))
 	}
 	start := time.Now()
@@ -98,7 +98,7 @@ func streamInterceptor(ctx context.Context, desc *grpc.StreamDesc, cc *grpc.Clie
 	}
 	if !credsConfigured {
 		opts = append(opts, grpc.PerRPCCredentials(oauth.TokenSource{
-			oauth2.StaticTokenSource(&oauth2.Token{AccessToken: fallbackToken}),
+			TokenSource: oauth2.StaticTokenSource(&oauth2.Token{AccessToken: fallbackToken}),
 		}))
 	}
 	s, err := streamer(ctx, desc, cc, method, opts...)
diff --git a/interop/client/client.go b/interop/client/client.go
index 2a9a95ae881..194c3766478 100644
--- a/interop/client/client.go
+++ b/interop/client/client.go
@@ -202,7 +202,7 @@ func main() {
 			}
 			opts = append(opts, grpc.WithPerRPCCredentials(jwtCreds))
 		} else if *testCase == "oauth2_auth_token" {
-			opts = append(opts, grpc.WithPerRPCCredentials(oauth.TokenSource{oauth2.StaticTokenSource(interop.GetToken(*serviceAccountKeyFile, *oauthScope))}))
+			opts = append(opts, grpc.WithPerRPCCredentials(oauth.TokenSource{TokenSource: oauth2.StaticTokenSource(interop.GetToken(*serviceAccountKeyFile, *oauthScope))}))
 		}
 	}
 	if len(*serviceConfigJSON) > 0 {