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.”
Check out the latest Premier League transfer news below...
1. Wolves keen on Palhinha
Wolverhampton Wanderers are ready to make an offer for Tottenham Hotspur target and Sporting Lisbon defensive midfielder Joao Palhinha. (Record)
2. Arsenal circle for Tielemans
Arsenal are close to wrapping up a £40m deal to sign Youri Tielemans from Leicester City this summer. (The Sun)
3. BOURNEMOUTH, ENGLAND - DECEMBER 11: Ben Brereton Diaz of Blackburn Rovers and Jack Stacey of AFC Bournemouth contest the ball during the Sky Bet Championship match between AFC Bournemouth and Blackburn Rovers at Vitality Stadium on December 11, 2021 in Bournemouth, England. (Photo by Warren Little/Getty Images)
West Ham are reportedly leading the race to sign Blackburn Rovers star Ben Brereton Diaz. (The Sun)
4. Villa hold Kamara talks
Aston Villa are making another push to sign Marseille talent Boubacar Kamara having held more talks with the free agent midfielder. Newcastle United and Leeds United have also been linked in the past. (Daily Mail)