diff --git a/mach.bat b/mach.bat
index 7258a0d79ce..2e76ecf92bc 100644
--- a/mach.bat
+++ b/mach.bat
@@ -4,5 +4,5 @@ where /Q py.exe
 IF %ERRORLEVEL% NEQ 0 (
   python mach %*
 ) ELSE (
-  py -2 mach %*
+  py -3 mach %*
 )