diff --git a/tests/test_marathon_lb.py b/tests/test_marathon_lb.py
index 9f3c1b0c..31dd85be 100644
--- a/tests/test_marathon_lb.py
+++ b/tests/test_marathon_lb.py
@@ -113,7 +113,6 @@ def test_config_env_template(self):
         ssl_certs = ""
         templater = marathon_lb.ConfigTemplater()
 
-        _environ = dict(os.environ)
         os.environ["HAPROXY_HTTP_FRONTEND_HEAD"] = '''
 frontend changed_frontend
   bind *:80
@@ -123,8 +122,7 @@ def test_config_env_template(self):
         config = marathon_lb.config(apps, groups, bind_http_https,
                                     ssl_certs, templater)
 
-        os.environ.clear()
-        os.environ.update(_environ)
+        os.environ.pop("HAPROXY_HTTP_FRONTEND_HEAD")
 
         expected = self.base_config + '''
 frontend changed_frontend