United have reportedly told Zaha that he is surplus to requirements at Old Trafford this season, and the winger is believed to have his heart set on a move back to Palace.
The 21-year-old played a part in United's pre-season tour of the US, and manager Louis van Gaal publicly praised him for quickly adapting to the new striking role that he was given.
However now it's understood that the Dutchman feels there is no room for Zaha in his first-team squad for the forthcoming Premier League season. United have more than enough strikers, and natural wingers might struggle to fit into Van Gaal's new 5-3-2 formation.
United's manager is also said to be in two minds whether to loan Zaha out or sell him permanently as Crystal Palace are said to be willing to do either.
The report claims that any loan deal will include an initial £2 million fee, plus a financial clause that will allow the London-based side to sign him back permanently at the end of his loan, should he impress.
The winger, who has also been courted but the likes of Newcastle United, QPR and West Ham, has had a difficult spell at United since arriving last summer for a fee of around £10 million plus £5 million worth of add-ons.
He was a Sir Alex Ferguson signing, but the legendary manager retired before the England international made it to Manchester. His successor David Moyes clearly didn't fancy Zaha, and he only made two appearances for the club before being shipped out on loan to Cardiff City in January.
Zaha ended up making 10 Premier League appearances for the Welsh side, but he failed to really impress and couldn't stop Ole Gunnar Solskjær's side from being relegated back to the Championship.