Zaha, who has been at Palace since he was eight, came to United's attention when he was named the Championship's player of the year last season.
He has continued to impress this term, scoring eight goals and making his England debut as a substitute against Sweden in November.
"Wilf has got all the plaudits and rightly so, he's had a great season and he had a great game against Brighton," said Palace skipper Mile Jedinak.
"But he knows, as we all do, that we can only achieve what we want to achieve as a team and we're all pushing towards the same goal."
If Palace do secure promotion at least defender Damien Delaney will only have to face Zaha twice, rather than every day in training.
"Sometimes when you're playing against him he drives you a bit mental, he can make you look a little bit foolish," said Delaney.
"But I don't think he knows any other way. He's one of those naturally gifted players - you give him the ball and tell him, 'go and enjoy yourself'.
"Obviously you have to give him a bit of structure in the team shape, but in general he's a one-off, such a good player."