Referee Michael Oliver was involved in a controversial decision in the FA Cup fifth round clash between Crystal Palace and Millwall, with the Video Assistant Referee (VAR) forced to intervene.

Just minutes into the London derby at Selhurst Park, Millwall goalkeeper Liam Roberts rushed out to try and clear the ball ahead of Jean-Philippe Mateta. While he did get to the ball first, the Millwall man’s high follow through led to him catching the Palace striker in the head with his foot as the two clashed.

At first, referee Michael Oliver appeared to let play continue. He did however stop the game when realising the seriousness of the injury to Mateta.

READ MORE: Donald Trump has three-word answer to Arsenal question as he meets Keir Starmer

READ MORE: Arsenal unearth new rising star after double breakthrough

During the stop in play, while Mateta was attended to, VAR recommended that the referee go over to the screen to decide on if a red card should be awarded. After reviewing the replay on the pitchside monitor, it didn’t take Oliver long to overturn his decision and award a straight red card to Roberts.

In a first for the FA Cup, the referee used an in stadium announcement to explain his decision, with the goalkeeper sent off for serious foul play.

Mateta was attended to by medical teams on the pitch for several minutes before being taken off on a stretcher. He appeared to be heading straight to the ambulance to take him to hospital for further treatment, and was replaced by former Arsenal man Eddie Nketiah.

Oliver has been involved in other controversial decisions so far this season. Earlier last month, he sent off Arsenal full-back Myles Lewis-Skelly in the game against Wolves, a decision that was later overturned on appeal by Arsenal.

Palace took advantage of their extra man by taking the lead in the 33rd minute through a Japhet Tanganga own goal. That lead was doubled by Daniel Munoz seven minutes later, Oliver awarded the goal, despite the offside flag being up, due to the ball coming off a Millwall defender.

The Lions halved the deficit with the final kick of the first half, when Wes Harding found the back of the net via a Ben Chilwell deflection.