diff --git a/synapse/app/appservice.py b/synapse/app/appservice.py

index 9a37384fb7..3348a8ec6d 100644
--- a/synapse/app/appservice.py
+++ b/synapse/app/appservice.py
@@ -117,8 +117,9 @@ class ASReplicationHandler(ReplicationClientHandler):
         super(ASReplicationHandler, self).__init__(hs.get_datastore())
         self.appservice_handler = hs.get_application_service_handler()
 
+    @defer.inlineCallbacks
     def on_rdata(self, stream_name, token, rows):
-        super(ASReplicationHandler, self).on_rdata(stream_name, token, rows)
+        yield super(ASReplicationHandler, self).on_rdata(stream_name, token, rows)
 
         if stream_name == "events":
             max_stream_id = self.store.get_room_max_stream_ordering()