Manchester United legend Wayne Rooney has strongly criticised Lisandro Martinez for his poor defensive effort during the Red Devils' 2-0 loss to Chelsea at Stamford Bridge on Saturday.
Rooney described the Argentine defender's attempt to stop Morgan Rogers' goal as 'horrendous', accusing him of failing to use his body to challenge the Chelsea forward.
The decisive moment came in the 50th minute when Rogers picked up possession around the centre circle before driving straight through Manchester United's defence and calmly lifting the ball over goalkeeper Senne Lammens.
Martinez endured a difficult afternoon, and his problems worsened towards the end of the encounter. He initially received a yellow card for pulling back Rogers before being sent off just 82 seconds later for catching Wesley Fofana with a raised arm while defending a corner.
Cole Palmer subsequently converted the resulting penalty, sealing Chelsea's 2-0 victory and extending Manchester United's disappointing run to nine matches without a win in all competitions.
The defeat also left United sitting 17th in the Premier League standings.
Speaking on The United Stand, Rooney, Manchester United's all-time leading goalscorer, analysed the defensive mistakes that allowed Rogers to score.
“The first goal for me was a killer for everyone. Rogers picks the ball up and just runs in a straight line. Yoro is out of position, which can happen because there was a turnover. Maguire does the right thing initially, but the closer Rogers gets, he has to get him and leave him out wide.”
The former England captain singled out Martinez for his failure to stop Rogers, describing the defender's challenge as unacceptable and comparing it to the kind of mistake that should not happen even at schoolboy level.
"And then Martinez comes across; his attempt at a tackle is horrendous; you wouldn't want schoolboys doing that.
“He goes in and just touches Rogers; he doesn't put any force into it; that's where you put your body across and try to knock him. He just waves his arm at him and lets him go through. That goal was horrendous.”
Meanwhile, Martinez will miss Manchester United's next Premier League fixture against Aston Villa on Sunday after his dismissal against Chelsea.
EPL: Wayne Rooney condemns Lisandro Martinez's errors in Man Utd, Chelsea 2-0 loss