In the aftermath of Manchester United's dramatic 3-2 defeat at Arsenal, former Old Trafford favourite Roy Keane singled out four players who underwhelmed as the Red Devils fell "well short" against the Gunners.
Eddie Nketiah's late, late winner was enough to prevent United from leaving Emirates Stadium with a share of the spoils. Sunday's reverse ended United's six-match unbeaten run, which had sparked hope they had turned a corner under Erik ten Hag.
But Keane has insisted that the defeat by Arsenal was a reminder that United have plenty of issues - and that certain players still aren't up to it. He told Sky Sports: "I think the last few days have been difficult with the dropping points last-minute against [Crystal] Palace and the defeat today. So, yeah, that’s what the game does to you.
"United weren’t at their best, but you think they could have hung on for the draw, take a point and move on, but it goes back to where United made progress. But then come the end of the game, [Luke] Shaw's still at left-back - question marks over him - [Aaron] Wan Bissaka, Fred's back in midfield. [Scott] McTominay... it's as if United haven't moved on from their problems of the past."
With the January transfer window still open, Mirror Football takes a look at who could replace those four players if United were to follow Keane's advice in the next few days...
Left-back
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Keane may have had a point regarding Luke Shaw in the past, but the United man has been in inspired form over the past few weeks. Shaw, 27, has caught the eye in his regular left-back role and as an emergency centre-back when United's squad was laid bare by a virus following the World Cup.
Given that Ten Hag signed Tyrell Malacia from Feyenoord to compete with Shaw for the left-back role last summer, it's unlikely that United would enter the market for another full-back option this month.
Right-back
Aaron Wan-Bissaka had been expected to leave Old Trafford this month, but it seems as though the former Crystal Palace man has played his way back into United's plans. Wan-Bissaka, 25, was at fault for Arsenal's opening goal on Sunday and there are no guarantees over his long-term future; even if United are open to keeping him now, a substantial bid could change that stance.
But Diogo Dalot is the club's first-choice right-back and that isn't likely to change anytime soon. If United were still planning ahead and open to bolstering their right-back options at the right price, then they could do worse than join Arsenal in the race for the highly-rated Real Valladolid prospect Ivan Fresneda.
Midfield
While Shaw and Dalot could be handed a reprieve this month, the same cannot be said for Scott McTominay and Fred - although United have made it clear that they are unwilling to sell the former amid transfer interest from Newcastle.
It's common knowledge that Ten Hag still has plans to overhaul United's midfield and it's likely that the Dutchman will resume his search for reinforcements in the summer, when the likes of Jude Bellingham and Declan Rice could be on the agenda. If Ten Hag does decide to act in January, then United will be shopping in a much smaller market given there are a dearth of funds available to them.
Leicester playmaker Youri Tielemans could be available for a knock-down price with just six months remaining on his deal while Juventus and United States midfielder Weston McKennie is also likely to be available this month despite a stellar showing at the World Cup.
