Manchester United face Villarreal in their first game without Ole Gunnar Solskjaer, who was sacked the morning after Saturday's embarrassing Premier League defeat to Watford.
Progression to the latter stages of the Champions League is at stake here, with caretaker manager Michael Carrick tasked with motivating a response out of the players.
Here's a look at the starting XI he could pick...
1. Goalkeeper & defenders
David de Gea (GK): Saved Ismaila Sarr’s penalty twice on Saturday but was helpless to do more as the team in front of him crumbled.
Aaron Wan-Bissaka (RB): A lack of genuine competition for the past 18 months have likely contributed to a drop in form.
Victor Lindelof (CB): When fit, the Swede has been the preferred stand-in for Raphael Varane, who continues to be missing with injury.
Harry Maguire (CB): Available here despite his red card in the Premier League on Saturday. Pressure is mounting on the skipper so he needs to deliver a big performance.
Alex Telles (LB): With Luke Shaw suffering a second head injury in as many weeks, the smart move is not to rush him back.
Donny van de Beek (CM): Made a big impact off the bench on Saturday and was a sole bright spark in an otherwise woeful team performance.
Fred (CM): Likely to return to the side after missing out following his return from South America during the international break.
Bruno Fernandes (AM): Wanted to make fans aware the blame for recent results lies with the players, but now he has to step up and perform.
Jadon Sancho (RW): Started to strike up an understanding with Ronaldo in the second half against Watford and put a few teasing crosses into the penalty area.
Cristiano Ronaldo (ST): His return has divided opinion. But the truth is that his goals have dragged United to the brink of qualifying for the last 16 – where would they be otherwise?
Jesse Lingard (LW): Desperately waiting for his chance and could finally get it. Marcus Rashford was seemingly only fit enough for half a game against Watford.