diff --git a/lib/web/fetch/body.js b/lib/web/fetch/body.js
index adfcb99302a..c46dec21ca5 100644
--- a/lib/web/fetch/body.js
+++ b/lib/web/fetch/body.js
@@ -60,7 +60,7 @@ function extractBody (object, keepalive = false) {
     // 4. Otherwise, set stream to a new ReadableStream object, and set
     //    up stream with byte reading support.
     stream = new ReadableStream({
-      async pull (controller) {
+      pull (controller) {
         const buffer = typeof source === 'string' ? textEncoder.encode(source) : source
 
         if (buffer.byteLength) {