diff --git a/lib/replicator.js b/lib/replicator.js
index 510ab2da..a8f8f9ce 100644
--- a/lib/replicator.js
+++ b/lib/replicator.js
@@ -1189,7 +1189,7 @@ class Peer {
   }
 
   _requestBlock (b) {
-    const { length, fork } = this.core.tree
+    const { prologue, length, fork } = this.core.tree
 
     if (this._remoteHasBlock(b.index) === false || fork !== this.remoteFork) {
       this._maybeWant(b.index)
@@ -1200,7 +1200,9 @@ class Peer {
       return false
     }
 
-    const req = this._makeRequest(b.index >= length, b.priority, b.index + 1)
+    const treeLength = (prologue && prologue.length > length) ? prologue.length : length
+
+    const req = this._makeRequest(b.index >= treeLength, b.priority, b.index + 1)
     if (req === null) return false
 
     this._sendBlockRequest(req, b)