Leicester manager Steve Cooper criticizes 'appalling human error' in VAR decision for Crystal Palace goal by Jean-Philippe Mateta

Steve Cooper has criticized the "unacceptable human error" he believes led to VAR selecting the wrong frame to validate Jean-Philippe Mateta's first goal in Leicester's match against Crystal Palace, however the PGMOL has denied his accusation.

The Foxes were 2-0 up at Selhurst Park on Saturday but Mateta's second-half double saw Palace come back to earn a 2-2 draw and extend Leicester's winless start to the season.

The first of Mateta's strikes was initially disallowed by the assistant referee's offside flag, until a VAR review overruled that decision and awarded Palace the goal.

Cooper says other angles have subsequently raised doubt over whether the wrong freeze-frame was chosen, and that Mateta was indeed offside when the ball was played to him.

Leicester showed the PGMOL other images they believe prove their case during a meeting on Monday, but News understands the refereeing body insisted no error was made and explained why it rejected the claims.

Speaking on Thursday, three days after that meeting, Cooper refused to back down, telling reporters: "We're over it now, it was an awful human error. We have seen images that show he clearly was offside, but they froze it at the wrong time.

"Everything seen has been a false image. We showed the Premier League that they used the wrong image. We had a massive error go against us, errors like that shouldn't happen and it's why we're changing to the semi-automated system.

"We felt very let down by it. We needed to stand up for the club and tell the Premier League what we thought."

What happened?

Leicester went into a 2-0 lead right at the start of the second half - but Crystal Palace struck back 86 seconds later through Mateta, who would go on to score a late equaliser from the penalty spot.

Mateta's first was initially flagged offside but a VAR check overturned that decision, with a screenshot from the VAR control room showing Mateta to be behind the leg of the Leicester defender nearest Tyrick Mitchell, who was crossing the ball from the left.

How are the lines generated?

The VAR officials in the Premier League freeze the match footage at the point of contact from the player passing to a team-mate potentially in an offside position and then use 3D lines to see whether the goal-scoring attacker is offside.

During the process, crosshairs can be used to select the furthest forward point of the attacker and the second deepest defender (most often the last defender, when the goalkeeper is in position).

If there is an issue with the technology and a clear decision can't be made, the on-field decision stands.

What about semi-automated offsides?

Earlier this year, Premier League clubs voted unanimously to bring in semi-automated offside technology, which was used at this summer's Euros. However, the system wasn't ready to implement at the start of this season, so will be launched in the coming months.

The technology uses cameras around the ground to track the ball and player movements and alerts VAR officials if there has been an offside prior to a key incident, such as a penalty, goal or red card.

What was the Ref Watch verdict?

Former Premier League referee Dermot Gallagher: "VAR felt he was just kept onside. The only authority we've got is the technology until semi-automated comes.

"The line says he's just onside, that's all we can go on. Every team plays to the same technology - if it says onside it's onside, if it says off it's off. In their view it's factual."