Ole Gunnar Solskjaer has revealed Edinson Cavani will miss Sunday's trip to West Ham - but may be in contention to return from injury in the EFL Cup tie with the Hammers next Wednesday.
Cavani has had a big impact when fit since joining United last summer, but has recently been struggling with what the club have described as a strain, picked up while with the club during the international break.
United go into the trip to the London Stadium off the back of a Champions League defeat to Young Boys, though are top of the Premier League on goals scored after four games. And while United have a strong squad of players to take into their trip to London, the Uruguayan will not be a member of the travelling party.
In a pre-match press conference, he said: "Edinson will hopefully start training with us after the weekend, maybe Monday, so maybe [he'll be] involved on Wednesday. He had a fantastic season last season with the impact he made when he got his fitness. He struggled with injuries early on.
"We feel that to get the best out of him this season we need to get him 100% fit and not rush him. We’ve got a strong squad that will cope with having to let players heal and not risk any further injuries.
"I see Edinson having a massive impact, he’s that type of personality and player. He can’t wait to play and he’s working really hard to get back on the pitch."
One player who may feature is Jesse Lingard, who was brought on in Switzerland on Tuesday only to play a short back pass which resulted in a winning goal for Young Boys. Lingard has since issued a post on social media apologising for his mistake, and Solskjaer was quick to defend the England international.
Solskjaer also revealed the club are in talks with Lingard over a new contract, given his deal expires in June next year.
"He’s got one year left on his contract and of course the club is talking to him and his dad," said Solskjaer. "We see him as a Man Utd player in the future as well.
"Jesse has come back into us after a great spell at West Ham; he showed his qualities, he's back into the England squad, scoring goals.
"We really want to see the best of Jesse this season, we support him and we hope to keep him here with us - he’s a red through and through."
Diogo Dalot also featured in the defeat to Young Boys following Aaron Wan-Bissaka's sending off, and Solskjaer admitted he's expecting the Portuguese full back to play a bigger role this season.
"Diogo has had a very good summer with being called up to Euros, he did well for Portugal Under-21s and had a season on loan in Milan and learned a lot.
"He kept fit, which was a big thing. And he’s got qualities that we look at trying to exploit more and more, of course he's got more experience. We’re not here just to loan out players for years and years. Last year's loan was was to give him experience and game time and I think he did well when he came on the other night."