diff --git a/django/db/models/query.py b/django/db/models/query.py
index 8bd981d..03ee312 100644
--- a/django/db/models/query.py
+++ b/django/db/models/query.py
@@ -463,6 +463,9 @@ class QuerySet(object):
         Returns a tuple of (object, created), where created is a boolean
         specifying whether an object was created.
         """
+        if callable(defaults):
+            defaults = defaults()
+
         lookup, params = self._extract_model_params(defaults, **kwargs)
         # The get() needs to be targeted at the write database in order
         # to avoid potential transaction consistency problems.
@@ -480,6 +483,9 @@ class QuerySet(object):
         specifying whether an object was created.
         """
         defaults = defaults or {}
+        if callable(defaults):
+            defaults = defaults()
+
         lookup, params = self._extract_model_params(defaults, **kwargs)
         self._for_write = True
         try: