diff --git a/src/ajax/script.js b/src/ajax/script.js
index be422adf3..2e937fe65 100644
--- a/src/ajax/script.js
+++ b/src/ajax/script.js
@@ -46,8 +46,6 @@ jQuery.ajaxTransport( "script", function(s) {
 
 				script = document.createElement("script");
 
-				script.async = true;
-
 				if ( s.scriptCharset ) {
 					script.charset = s.scriptCharset;
 				}
diff --git a/src/manipulation/_evalUrl.js b/src/manipulation/_evalUrl.js
index 0fdacbcee..007e7293c 100644
--- a/src/manipulation/_evalUrl.js
+++ b/src/manipulation/_evalUrl.js
@@ -8,6 +8,8 @@ jQuery._evalUrl = function( url ) {
 		type: "GET",
 		dataType: "script",
 		cache: true,
+
+		// Make this explicit, since user can override this through ajaxSetup (#11264)
 		async: false,
 		global: false,
 		"throws": true