Shelvey and Willock missed this afternoon’s 5-0 defeat to Manchester City at the Etihad Stadium.
And Eddie Howe revealed after the game that he feared that their seasons were over.
“Joe’s had a knee problem for a couple of months,” said United’s head coach.
“We felt that it had gone, but it came back against Liverpool last week, so it looks like his season’s over, and Jonjo’s picked up a calf injury.”
In better news, Kieran Trippier made his return from injury off the bench on Sunday afternoon.
It was the first time Trippier has featured for United since fracturing his metatarsal against Aston Villa on February 13.
The match also saw Callum Wilson make his comeback from a calf injury that had kept him out since late December.
“It has been a long three months,” Trippier admitted. “Obviously people don’t see the work that injured players put in – certainly Cal – who deserves huge credit for the set-backs he’s had and how he’s bounced back from them.
“It’s been hard but when you’re injured you just need to support your teammates on the pitch and we’ve done that and the lads have been unbelievable without us.
“We hope we can come back into the team, on the bench or wherever it may be and help us win the next two games.”
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