He only scored seven for the Latics last season and, including the deflected effort against CSKA Moscow that UEFA have credited him with, the Ecuador international now has four for United.
He is also starting to impose himself on games, with his forceful running unhinging a disappointing Everton outfit who seemed intent on containment.
"Antonio is a top-class player," said Fletcher. "He is getting used to the way we play and he was in the groove again.
"He is a really strong physical lad who can get goals. We have seen that in training and I believe he is going to get a lot for Manchester United."