KOBBIE MAINOO ranted to Manchester United team-mates Casemiro and Antony moments after going off injured in their 3-0 loss to Tottenham… before the Red Devils then messed up the substitution.

England international Mainoo, 18, suffered a knock moments after Bruno Fernandes’ red card and was swiftly replaced by Mason Mount.

Kobbie Mainoo went off injured in the first half and was replaced by Mason Mount

He ranted to Casemiro and Antony after being substituted

It was unclear what exactly Mainoo was furious about

Manchester United then messed up the substitution and momentarily played with nine men

As he trudged off the pitch, he could be seen remonstrating with substitutes Casemiro and Antony.

The Three Lions star appeared to be angry at a particular incident on the pitch, though it is unclear specifically what he was gesturing about.

Man Utd then made matters worse as play resumed before Mount had come on the pitch.

It meant they were temporarily defending with just nine players as Mount waited by the touchline.

After the ball went dead seconds later, the ex-Chelsea man was finally allowed to enter the fray.

The embarrassing mistake occurred at the end of a nightmare first half for Erik ten Hag’s side.

Less than three minutes into the game, Tottenham had taken the lead thanks to a cross from Brennan Johnson, which came after Micky van de Ven swaggered past four Manchester United defenders.

The team led by Ange Postecoglou dominated the whole match and ought to have been more ahead until Fernandes was sent off for a reckless challenge on James Maddison just before halftime.

The legendary Manchester United player Gary Neville was brutal in his assessment of Erik ten Hag’s team, even before they gave up goals from Dominic Solanke and Dejan Kulusevski in the second half.

After labelling the Red Devils “helpless” and “hopeless”, Neville added: “I can’t believe what I’m watching, it’s awful.”

And ex-Spurs midfielder Jamie Redknapp said: “Spurs have been excellent.

“But United have been abject. No confidence, no identity. It has been so poor from them.”

Mainoo was clearly upset as he trudged down the tunnel