With the transfer window now slammed shut, attention fully turns to matters on the pitch for the second half of the season. Manchester United return to action on Friday night as they kick-off the FA Cup fourth round schedule.

Their upcoming clash sees them up against former interim manager Ruud van Nistelrooy for the first time since his exit from Old Trafford. The Dutchman brings his Leicester City team to his former home with both teams looking to bounce back from defeats in their last Premier League outings.

United overcame Arsenal on penalties to book their spot in the fourth round. Leicester, meanwhile, recorded a 6-2 win over Championship side QPR to make it to Old Trafford.

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The game could, potentially, see both sides make changes to their usual starting line-ups, but what is the injury list looking like for Ruben Amorim? Here's a look at the latest United injury situation at Carrington;

Lisandro Martinez

Injury: Knee

The centre-back was stretchered off in tears in last weekend's reverse against Crystal Palace. Reports in his home nation state that Martinez has suffered a knee ligament injury which is expected to rule him out for the remainder of the season - and perhaps even into next campaign.

What Amorim has said: "We are going to see in the next days, but I think it's a serious situation. Not just a great player, but a strong character in the dressing room. In this moment, it's hard on us, but now it's time for us to help Licha, like he helps us every day. When you are a player, you know when it's serious."

Return date: TBC

Luke Shaw

Injury: Muscular

Shaw returned to training ahead of last week's Europa League clash against FCSB, but he was not included in the squad for that game or the weekend's Premier League clash against Palace as he builds up his fitness.

What Amorim has said: "It could take a little bit more time. I think he needs to train more, to spend time with his teammates playing small-sided games, and not just working alone. When I feel it is the right moment, we will start with some minutes in the games."

Potential return date: February 7 vs Leicester City (H)

Mason Mount

Injury: Leg

Mount was forced off in the first half of the Manchester derby back in December. It was confirmed a few days later that he would be on the side-lines for several weeks.

What Amorim has said: "Several weeks. I don't know the exact date, but it's going to be for long. And that's it... It's part of football, and you continue."

Return date: TBC

Jonny Evans

Injury: Muscular

Evans has been out of action since December - after suffering a muscular injury. His latest appearance for the club came in the Carabao Cup quarter-final defeat against Tottenham back in December, a match in which he was also on the scoresheet.

What Amorim has said: n/a

Return date: TBC