The England international was injured in the Emirates FA Cup semi-final against Coventry City and missed the win over Sheffield United and draw with Burnley.
Although it was thought the forward would not be involved again at Crystal Palace on Monday night, the manager told MUTV's Mark Sulivan that there is an outside chance he could prove his fitness in time.
Bruno Fernandes and Scott McTominay are also battling against the clock, while Jonny Evans will definitely return to the squad as long as he continues training without any issues over the weekend.
"We have some players with question marks," Erik told club media at Carrington.