The German World Cup winner has been linked with a move to Old Trafford, but Redknapp questions whether he would leave Bayern Munich.
Dutchman Van Gaal is keen to add quality to his side for next season as United return to the Champions League and potentially look to mount a Premier League title challenge.
Muller would, of course, be an excellent addition to his side, and Redknapp agrees, saying it’s not hard to see why United are interested but questioning whether the player and his current club would sanction a move.
“But would he want to go and would Bayern be prepared to let him go? However, if Sergio Ramos wants to leave Real Madrid for United then it’s clear the attraction of playing in the Premier League is still alive and well.”
Where would Muller fit in at Manchester United?
Where Muller would fit into the United side should he move to Old Trafford would be the first challenge Van Gaal would have to overcome.
He already has several attacking midfielders at his disposal, with the likes of Juan Mata, Angel di Maria and Marouane Fellaini all vying for places, while Memphis Depay has also been added this summer.
They are, though, short on forwards, so perhaps Muller could be used in that position, with the 25-year-old certainly capable of finding the back of net on a regular basis and having filled that role for Bayern in recent seasons.