Millwall goalkeeper Liam Roberts was shown a red card early in the FA Cup tie against Crystal Palace after a horrific Kung fu kick on Jean-Philippe Mateta. The 30-year-old came rushing off his line to meet a long ball over the top to Mateta and first made contact with the ball. However, the Englishman led with his foot - almost in a karate kick style - which was reckless but clearly not intentional, and he collided with Mateta with some force on the follow-through.

The French striker collapsed to the ground in a heap and did not immediately get up, with medical staff rushing to his aid. He was given oxygen on the ground during the stoppage, which lasted several minutes. While Palace's medical staff attended to their stricken player, referee Michael Oliver - who did not initially show a red card - was advised to review the incident on the pitchside monitor by VAR official Nick Hopton. After a brief review, Oliver announced via the PA system that Roberts would be shown a red card for serious foul play.

After a lengthy delay, it was clear that Mateta would be unable to continue as he was stretchered off the pitch, with an ambulance waiting to take him to hospital. The home fans gave him a standing ovation, while ugly chants from the Millwall fans emanated from the away end.

While the Frenchman was clearly in a bad way and receiving treatment on the pitch, a group of Millwall fans at Selhurst Park appeared to chant: "Let him die, let him die, let him die."

BBC commentator Jonathan Pearce, who was behind the microphone for the game, was left shocked by the obscene chants from some Millwall fans and made his disgust known: "Millwall fans are not endearing themselves with anyone with those chants about Mateta."

TV cameras panned to Palace chairman Steve Parish sitting in the directors' box. And the Eagles supremo, who looked concerned for his player, gesticulated to other members of staff beside him and re-enacted the tackle.

Palace boss Oliver Glasner was forced to make an early change, replacing him with Eddie Nketiah, while Millwall sacrificed Luke Cundle for reserve stopper Lukas Jensen.

Nketiah had the ball in the net moments after coming on, before the offside flag went up against the Palace forward. But the hosts did take a deserved lead on 35 minutes after Japhet Tanganga diverted a Will Hughes cross-shot into his own net.

It was 2-0 just before half time when Daniel Munoz stabbed home from close range after VAR overturned the on-field decision to rule out the goal, as the ball clearly came off Tanganga rather than a Palace player.

There were 13 minutes of stoppage time added on at the end of the first half due to the amount of time Mateta was down, in addition to other injuries during a stop-start half.