diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py
index edaa223808..f15e4ac2f2 100644
--- a/django/db/models/sql/query.py
+++ b/django/db/models/sql/query.py
@@ -738,7 +738,7 @@ class Query(object):
         Returns True if the join was promoted.
         """
         if ((unconditional or self.alias_map[alias][NULLABLE]) and
-                self.alias_map[alias] != self.LOUTER):
+                self.alias_map[alias][JOIN_TYPE] != self.LOUTER):
             data = list(self.alias_map[alias])
             data[JOIN_TYPE] = self.LOUTER
             self.alias_map[alias] = tuple(data)