The Manchester United squad have travelled down to the capital for Sunday's mouthwatering title showdown with Arsenal.
United have recovered from a torrid start to the season and sit third in the Premier League ahead of their meeting with the Gunners, who are eight points clear of Erik ten Hag's side.
Prior to their midweek draw against Crystal Palace, people in some quarters had claimed that Manchester United had muscled their way into the title race following their impressive win over Manchester City last weekend.
And a win at the Emirates this weekend would certainly ramp up the pressure on Arsenal, who have only dropped points three times this term.
United travel to north London in fine form, but they will face the league leaders without Casemiro, who picked up his fifth booking of the season in the final stages of Wednesday night's match at Selhurst Park.
Given that the former Real Madrid enforcer's integration into the team coincided with United's upturn in form, Casemiro will be sorely missed by United, who will be forced to shuffle things up against Arsenal.
Ten Hag has given little away in the build-up to the match in terms of who might replace the multi-time Champions League winner. He did, however, stress that United have the strength in depth to cope without the Brazilian at the weekend.
Speaking on the eve of the game, Ten Hag said: "I think we have good squad, a competing squad. As you know, Casemiro is absent, but for the rest, we have a good team who has to battle with Arsenal. We have to go head-to-head, and we are convinced we are in a good way."
United's team, minus Casemiro, were snapped travelling down to London by train on Saturday. The Manchester Evening News revealed that Anthony Martial and Diogo Dalot were also absent from the travelling party.
Scott McTominay is perhaps the most likely candidate to step in for Casemiro; the Scottish midfielder retained his spot ahead of the veteran for weeks while the United new boy acclimatised to life at Old Trafford.
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McTominay, alongside Christian Eriksen, played as one half of a double pivot against Arsenal in the reverse fixture earlier in the season, which United won 3-1.
Fred was introduced from the bench in that match but has muscled his way back into Ten Hag's first-team plans in recent weeks. After impressing alongside Casemiro, the former Shakhtar Donetsk man could line up alongside McTominay or Christian Eriksen, who has also impressed from a deeper role since completing his move to United back in the summer.
Speaking earlier in the week, Gary Neville admitted that Casemiro's absence made Arsenal favourites ahead of Sunday's match.
He told Sky Sports: "They [United] beat them [Arsenal] without Casemiro last time. They're going to have to play extremely well, defend well, especially in the first half hour when Arsenal are electric, but they don't have a great bench.
"If you get through that first period of the game, what you're going to face is what you're going to face later on in the game. They had that problem against Newcastle, who defended really well against them. But Arsenal are in great form, massive favourites for the game with Casemiro out.
"United have got to hang in there for the first part of the game and they are dangerous on the counter-attack. But without Casemiro, I expect Arsenal to win on Sunday."