Erik ten Hag discovered Manchester United's most important defender in just four days

Manchester United played Leeds twice in a rare double-header Premier League fixture last week and they secured four points from those two fixtures. Both performances weren't vintage but Sunday's win at Elland Road was a crucial victory.

But what did Erik ten Hag learn from those matches? It seems he would have been sent a reminder about who his most valued defender is, as he was named on the bench to play Leeds at the weekend and his absence from the team was obvious.

Lisandro Martinez was rested on Sunday ahead of Thursday's match against Barcelona at Camp Nou, even though it's a fixture which he's unavailable for due to picking up three yellow cards in the Europa League group stage.

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Although United recorded a clean sheet against Leeds at Elland Road, that looked unlikely for large periods of the game. David de Gea made a couple of key interventions and the hosts, who are struggling in the league, should have found the net.

Luke Shaw and Harry Maguire were the preferred centre-back pairing for the match and the latter highlighted why Martinez was signed for £46.8million, rising to £55.3m, in the summer and why his own days at Old Trafford are numbered.

Maguire, perhaps unnerved by the hostile atmosphere, was awful with the ball throughout the contest. His passing was sloppy, wayward and unconvincing, which meant the build-up play was affected and uncharacteristically poor.

United won the match 2-0 thanks to brilliance from Marcus Rashford and Alejandro Garnacho, but they could not leave their own half for portions of the first 45 minutes, particularly, in which Leeds pressed well and Maguire struggled to consistently find a pass.

Whilst the