Manchester United manager Erik ten Hag might have hinted at partnership vs Luton

"The build-up is not that fluid when one of them is playing from the left centre-back position," Erik ten Hag said of Harry Maguire and Raphael Varane.

"Because I think Licha (Martinez), obviously, Luke Shaw, obviously, Jonny Evans and Victor Lindelof are right-footed, but they can play really comfortably with their left and make the right angles."

No mention of Varane there. Varane and Maguire have started together twice this season, though Maguire has only been partnered by Lindelof once and Newcastle United ran riot at Old Trafford.

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"I was very happy with the game in Copenhagen," Ten Hag stressed on Sunday. "I think it was our best minutes for as long as it was 11v11. It was a very good midfield balance, but there was a good balance all over the team.

"We played very well and it is just the way we want to see. We have to build on that.”

Few United fans would disagree with that assessment. They impressed for 70-odd minutes in Denmark but collapses at the end of both halves cost them.

Given the quality of United's performance before Marcus Rashford's red card, the one change to the line-up could be enforced with Jonny Evans out.

Diogo Dalot was alert for 83 minutes but then he dozed off for Copenhagen's 83rd-minute equaliser that sparked another collapse from United.

Ten Hag's preference for two right-footers and two left-footers in his back four is undermined by the omission of loanee Sergio Reguilon. Since Reguilon resumed training, he has started two of United's last six games and Lindelof had a dicey stint at left-back before Dalot switched there.

United have a break clause in Reguilon's deal. If