The Dutchman brought in six players in the summer, with three of them predominantly playing in central midfield. Ander Herrera, Angel Di Maria and Daley Blind have all impressed this season, but the spending in that one area was in part down to the absence of one key player.
Michael Carrick suffered an ankle injury almost as soon as van Gaal arrived at Old Trafford, but after successful surgery in the summer, he's almost back to full fitness.
United legend Bryan Robson says that the 33-year-old has been sorely missed in the United midfield, but wouldn't play him in Sunday's big clash against Manchester City.
"Michael's been a big miss to United," said Robson. "When he was injured last season he was a big loss to us and again this season."
"He's an intelligent player who gets into the right areas. He's about 6ft 2ins and defensively at set plays is very good. He intercepts things very well. That's why he's important as well."
"The only thing the manager has to be careful of is, if there are a few players coming back from injury, you don't want to play too many who are a little bit rusty because it's a derby game, it's going to be a million miles an hour, loads of passion and pace, so the lads who have been playing week in week out are probably more up to speed with the game," he added.