diff --git a/src/display/api.js b/src/display/api.js
index aaedfcf3b..c0e54f2a8 100644
--- a/src/display/api.js
+++ b/src/display/api.js
@@ -357,7 +357,7 @@ function getDocument(src) {
     task._worker = worker;
   }
 
-  const fetchDocParams = {
+  const docParams = {
     docId,
     apiVersion:
       typeof PDFJSDev !== "undefined" && !PDFJSDev.test("TESTING")
@@ -398,9 +398,16 @@ function getDocument(src) {
       if (task.destroyed) {
         throw new Error("Loading aborted");
       }
+      if (worker.destroyed) {
+        throw new Error("Worker was destroyed");
+      }
 
-      const workerIdPromise = _fetchDocument(worker, fetchDocParams);
-      const networkStreamPromise = new Promise(function (resolve) {
+      const workerIdPromise = worker.messageHandler.sendWithPromise(
+        "GetDocRequest",
+        docParams,
+        data ? [data.buffer] : null
+      );
+      const networkStreamPromise = new Promise(resolve => {
         let networkStream;
         if (rangeTransport) {
           networkStream = new PDFDataTransportStream(rangeTransport, {
@@ -451,6 +458,9 @@ function getDocument(src) {
           if (task.destroyed) {
             throw new Error("Loading aborted");
           }
+          if (worker.destroyed) {
+            throw new Error("Worker was destroyed");
+          }
 
           const messageHandler = new MessageHandler(
             docId,
@@ -474,31 +484,6 @@ function getDocument(src) {
   return task;
 }
 
-/**
- * Starts fetching of specified PDF document/data.
- *
- * @param {PDFWorker} worker
- * @param {Object} source
- * @returns {Promise<string>} A promise that is resolved when the worker ID of
- *   the `MessageHandler` is known.
- * @private
- */
-async function _fetchDocument(worker, source) {
-  if (worker.destroyed) {
-    throw new Error("Worker was destroyed");
-  }
-  const workerId = await worker.messageHandler.sendWithPromise(
-    "GetDocRequest",
-    source,
-    source.data ? [source.data.buffer] : null
-  );
-
-  if (worker.destroyed) {
-    throw new Error("Worker was destroyed");
-  }
-  return workerId;
-}
-
 function getUrlProp(val) {
   if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("MOZCENTRAL")) {
     return null; // The 'url' is unused with `PDFDataRangeTransport`.