python
diff --git a/cherry_picker/cherry_picker/cherry_picker.py b/cherry_picker/cherry_picker/cherry_picker.py
@@ -422,7 +422,7 @@ def get_base_branch(cherry_pick_branch):
     """
     return '2.7' from 'backport-sha-2.7'
     """
-    prefix, sep, base_branch = cherry_pick_branch.rpartition('-')
+    prefix, sha, base_branch = cherry_pick_branch.split('-', 2)
     return base_branch
 
 

diff --git a/cherry_picker/cherry_picker/test.py b/cherry_picker/cherry_picker/test.py
@@ -33,15 +33,16 @@ def changedir(d):
 
 
 def test_get_base_branch():
+    # The format of cherry-pick branches we create are "backport-{SHA}-{base_branch}"
     cherry_pick_branch = 'backport-afc23f4-2.7'
     result = get_base_branch(cherry_pick_branch)
     assert result == '2.7'
 
 
-def test_get_base_branch_without_dash():
-    cherry_pick_branch ='master'
+def test_get_base_branch_which_has_dashes():
+    cherry_pick_branch ='backport-afc23f4-baseprefix-2.7-basesuffix'
     result = get_base_branch(cherry_pick_branch)
-    assert result == 'master'
+    assert result == 'baseprefix-2.7-basesuffix'
 
 
 @mock.patch('subprocess.check_output')