diff --git a/src/backend.c b/src/backend.c
index b305ec0c8..4d47c9430 100644
--- a/src/backend.c
+++ b/src/backend.c
@@ -1581,6 +1581,14 @@ int connect_server(struct stream *s)
 	if ((srv_cs->flags & CS_FL_EOI) && !(si_ic(&s->si[1])->flags & CF_EOI))
 		si_ic(&s->si[1])->flags |= (CF_EOI|CF_READ_PARTIAL);
 
+	/* catch all sync connect while the mux is not already installed */
+	if (!srv_conn->mux && !(srv_conn->flags & CO_FL_WAIT_XPRT)) {
+		if (conn_create_mux(srv_conn) < 0) {
+			conn_full_close(srv_conn);
+			return SF_ERR_INTERNAL;
+		}
+	}
+
 	return SF_ERR_NONE;  /* connection is OK */
 }