Liverpool - Manchester United manager Ole Gunnar Solskjaer said he may be forced to look for a short-term fix in the transfer market this month to compensate for the loss of top scorer Marcus Rashford for at least six weeks.
The England international suffered a stress fracture in his back during a substitute appearance against Wolves in the FA Cup on Wednesday.
Speaking after United's 2-0 defeat to Liverpool at Anfield on Sunday, Solskjaer said Rashford's absence, allied to long-term injuries for midfielders Paul Pogba and Scott McTominay, may force the club into action in the two weeks before the transfer window closes.
The Red Devils have been strongly linked with a move for Sporting Lisbon midfielder Bruno Fernandes.
"The permanent signings we are looking for, those targets are not going to change because we've got players injured for the next two or three months," said Solskjaer. "There might be some short-term deals we have to do."
Rashford's absence is a huge blow to United's hopes of challenging for a top-four finish in the Premier League and in three cup competitions.
The 22-year-old has netted 19 times in his best ever goalscoring season and is not expected back until after the March international break.
"He's suffered a bad injury," added Solskjaer, whose side sit fifth in the table, five points off the top four.
"It will probably be six weeks before you can get going and then he's got to get match fit."
News of Rashford's injury is also another concern for England manager Gareth Southgate with Euro 2020 on the horizon.
The Three Lions already have an injury doubt over captain Harry Kane, who has undergone surgery on a hamstring tear and will be sidelined until at least April.