diff --git a/runbot_merge/github.py b/runbot_merge/github.py
index 76314692..2554a28c 100644
--- a/runbot_merge/github.py
+++ b/runbot_merge/github.py
@@ -124,7 +124,6 @@ class GH(object):
             assert len(c['parents']) == 1, "can't rebase commits with more than one parent"
             tmp_msg = 'temp rebasing PR %s (%s)' % (pr, c['sha'])
             c['new_tree'] = self.merge(c['sha'], dest, tmp_msg)['tree']['sha']
-        self.set_ref(dest, original_head)
 
         prev = original_head
         for c in commits: