Erik ten Hag has defended his decision to start Casemiro in Wednesday's 1-1 draw against Crystal Palace even though the Manchester United midfielder picked up a booking that rules him out of Sunday's Premier League showdown with leaders Arsenal.
Casemiro's yellow card for fouling Wilfried Zaha triggered an automatic one-match ban after accruing five already this campaign.
United were denied a 10th consecutive win - which would have been a first since 2009 - by Michael Olise's stoppage-time free-kick after Bruno Fernandes had given them a first-half lead at Selhurst Park.
The draw also meant United missed out on the chance to leapfrog crosstown rivals Manchester City into second place in the table and leaves them eight points behind Arsenal ahead of Sunday's clash at the Emirates Stadium.
Casemiro has been a key component to United's revival this season after signing for the Red Devils last August from Real Madrid for a fee that could rise to £70 million.
United manager Ten Hag said there was no way he could leave out Casemiro against Palace regardless of any possible suspension.
Crystal Palace v Man United ratings
"This game was important. Every game is important," Ten Hag said.
"Every game in the Premier League is a top game. Casemiro is obviously a really important player for us, and he is one of the reasons that we are in the position that we are now. That's Casemiro.
"But last time we beat Arsenal without Casemiro, so we have a squad, so we have to fill that gap and make a proper plan and the squad have to fill it and make sure that there is a team. We already showed how to beat Arsenal."
Casemiro came on as a late substitute in United's 3-1 victory over the Gunners in September, with Marcus Rashford's brace and an Antony strike making the difference at Old Trafford.
Palace boss Patrick Vieira was pleased to pick up the point and insisted he was focusing on the Eagles’ next meeting in their tough run against top sides rather than his former club’s title chase.
“I have enough on my plate thinking about Newcastle,” the former Arsenal midfielder said.
“[Arsenal and United] will be a good game of football. I think two teams who [hope] to play Champions League football or winning the title.
“I think both teams can win the league because of the quality of players that they have. So I’ll be like you, watching the game.”
Palace later confirmed a second-half pitch invader, who forced play to be temporarily halted and took a selfie with Casemiro, was arrested.
“A single individual entered the field of play before being led away by security and was later arrested,” a club statement read.