diff --git a/system_tests/test_compute_engine.py b/system_tests/test_compute_engine.py
index ceba0f7..2d6f42c 100644
--- a/system_tests/test_compute_engine.py
+++ b/system_tests/test_compute_engine.py
@@ -14,6 +14,7 @@
 
 import pytest
 
+import google.auth
 from google.auth import _helpers
 from google.auth import compute_engine
 from google.auth.compute_engine import _metadata
@@ -36,3 +37,11 @@
     info = token_info(credentials.token)
     info_scopes = _helpers.string_to_scopes(info['scope'])
     assert set(info_scopes) == set(credentials.scopes)
+
+
+def test_default(verify_refresh):
+    credentials, project_id = google.auth.default()
+
+    assert project_id is not None
+    assert isinstance(credentials, compute_engine.Credentials)
+    verify_refresh(credentials)
diff --git a/system_tests/test_default.py b/system_tests/test_default.py
index 0e0bcc6..c64a826 100644
--- a/system_tests/test_default.py
+++ b/system_tests/test_default.py
@@ -19,7 +19,7 @@
 EXPECT_PROJECT_ID = os.environ.get('EXPECT_PROJECT_ID')
 
 
-def test_explicit_credentials(verify_refresh):
+def test_application_default_credentials(verify_refresh):
     credentials, project_id = google.auth.default()
 
     if EXPECT_PROJECT_ID is not None: