diff --git a/test-requirements.txt b/test-requirements.txt
index 17df2c5..e85b144 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -5,7 +5,7 @@ hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
 
 coverage!=4.4,>=4.0 # Apache-2.0
 fixtures>=3.0.0 # Apache-2.0/BSD
-mock>=2.0 # BSD
+mock>=2.0.0 # BSD
 python-subunit>=0.0.18 # Apache-2.0/BSD
 sphinx>=1.6.2 # BSD
 testrepository>=0.0.18 # Apache-2.0/BSD