LONDON, England -- Manchester United manager Ole Gunnar Solskjaer fears striker Marcus Rashford could be sidelined "for a while" after suffering a groin injury during the 2-0 defeat to West Ham.
Rashford limped off in the second half leaving United to play for the final 30 minutes at the London Stadium with Jesse Lingard at centre-forward.
Solskjaer is hopeful of having Martial or Greenwood available for the Carabao Cup tie with Rochdale at Old Trafford on Wednesday and both back for Arsenal's visit on Monday.
"We will scan him [Rashford] tomorrow," Solskjaer said.
"He felt his groin so probably be out for a little while. I can update you later when I know a little more.
"It is just one of these moments. We've had, histrionically, loads of centre-backs of the last few years struggling with injuries.
"At the moment it is strikers. Hopefully Mason and Anthony will be back for Arsenal and hopefully one for Rochdale."
Injuries have left Solskjaer particularly short up front but after defeat to West Ham, Solskjaer defended his decision to let Alexis Sanchez sign for Inter Milan on loan following the close of the Premier League transfer window after already selling Romelu Lukaku to the Italian side earlier in the summer.
"We made a decision on that," said Solskjaer.
"I still think that was the best one for us, and Alexis. We agreed on that one."
It is United second successive away defeat to West Ham after losing 3-1 at the London Stadium last season.
Jose Mourinho oversaw that result and, working as a Sky Sports pundit on Sunday, said he had seen "no improvement" under Solskjaer.
"I think he has got a right to his opinion," replied the Norwegian when asked about Mourinho's comments.
"We lost here last year, it is always a difficult ground to go to. We hoped to do better than we did. The key moments they grasped, we didn't. We just didn't take the chances when we had them.
"This group, they want to do what we are trying to do.
"There are key moments in games, and maybe a bad decision or pass but the attitude and desire is there -- that is not the problem. It is the quality in our decision making and execution."