diff --git a/django/contrib/mongodb/base.py b/django/contrib/mongodb/base.py
index 54552b8a03..1e5529d98d 100644
--- a/django/contrib/mongodb/base.py
+++ b/django/contrib/mongodb/base.py
@@ -76,8 +76,9 @@ class DatabaseWrapper(BaseDatabaseWrapper):
         return self.connection[self.settings_dict["NAME"]]
 
     def close(self):
-        self._connection.disconnect()
-        self._connection = None
+        if self._connection is not None:
+            self._connection.disconnect()
+            self._connection = None
     
     
     ###########################
diff --git a/tests/regressiontests/mongodb/tests.py b/tests/regressiontests/mongodb/tests.py
index a39aec29d1..c87a4b18d4 100644
--- a/tests/regressiontests/mongodb/tests.py
+++ b/tests/regressiontests/mongodb/tests.py
@@ -1,3 +1,4 @@
+from django.db import connection
 from django.db.models import Count, F
 from django.test import TestCase
 
@@ -337,3 +338,8 @@ class MongoTestCase(TestCase):
             ],
             lambda g: g.name,
         )
+    
+    def test_close(self):
+        # Ensure that closing a connection that was never established doesn't
+        # blow up.
+        connection.close()