diff --git a/google-auth-library-java/oauth2_http/javatests/com/google/auth/oauth2/ServiceAccountCredentialsTest.java b/google-auth-library-java/oauth2_http/javatests/com/google/auth/oauth2/ServiceAccountCredentialsTest.java
index ed26a0af3c6f..3c772801d789 100644
--- a/google-auth-library-java/oauth2_http/javatests/com/google/auth/oauth2/ServiceAccountCredentialsTest.java
+++ b/google-auth-library-java/oauth2_http/javatests/com/google/auth/oauth2/ServiceAccountCredentialsTest.java
@@ -1762,6 +1762,16 @@ void createScopes_existingAccessTokenInvalidated() throws IOException {
     assertNull(newAccessToken);
   }
 
+  @Test
+  void getRequestMetadata_withUniverseAndDelegation_throws() {
+    ServiceAccountCredentials credentials =
+        createDefaultBuilderWithKey(OAuth2Utils.privateKeyFromPkcs8(PRIVATE_KEY_PKCS8))
+            .setUniverseDomain("example.com")
+            .setServiceAccountUser("user@example.com")
+            .build();
+    assertThrows(IOException.class, () -> credentials.getRequestMetadata(CALL_URI));
+  }
+
   private void verifyJwtAccess(Map<String, List<String>> metadata, String expectedScopeClaim)
       throws IOException {
     assertNotNull(metadata);