The Brazilian came from the bench on the hour mark against the Rs and helped the Red Devils come from behind to post a 3-1 victory.
And, in recognition of the midfielder’s vital contribution, Sir Alex revealed that he will be rewarded with a starting spot against the Hammers.
|BENITEZ IS A LUCKY MAN - FERGIE
|13/2||Manchester United are 13/2 with bet365 to beat West Ham 3-0
"I thought his performance was outstanding. He took the game by the scruff of the neck and he was so positive and determined in his play that he picks himself on Wednesday."
The 70-year-old also revealed that Antonio Valencia will face a late fitness test on a hip injury, whilst Nani is set to miss out with a hamstring problem.
"We'll see what Antonio is like today and tomorrow. Nani is still going to be out [but] Chris Smalling and Phil Jones were on the bench on Saturday and they're available," he continued.
"It's good to have them as back-up and in the back four things are much healthier. We've got plenty of options in the midfield and up front – it's just the two wide positions [where we have problems in terms of availability]."