diff --git a/lib/bcoin/peer.js b/lib/bcoin/peer.js
index 0912f463..377d5fd1 100644
--- a/lib/bcoin/peer.js
+++ b/lib/bcoin/peer.js
@@ -1793,6 +1793,9 @@ Peer.prototype.sync = function sync(callback) {
   if (!this.pool.syncing)
     return;
 
+  if (!this.ack)
+    return;
+
   if (this.syncSent)
     return;