VAR has made four mistakes in the Premier League so far this season, including two involving Cherries, head of top-flight refereeing Mike Riley has admitted.

The incidents in question concern Youri Tielemans escaping punishment for a dangerous challenge on Callum Wilson at Leicester and Jefferson Lerma tripping David Silva against Man City at Vitality Stadium.

The other two errors cited were Fabian Schar's goal for Newcastle being allowed to stand against Watford and the decision not to award West Ham a penalty when Sebastian Haller went down against Norwich.

"We are learning as we go along and we are constantly improving," Riley told Sky Sports.

"Out of the four match rounds, there have been some really good examples where we have intervened.

"There have been six incidents where VAR has advised the referee and we have got a better decision as a result.

"There were four incidents where VAR didn't intervene and had they done, we would have a better understanding of the role VAR plays in the game.

"(The mistakes) are all about the judgement of VAR and the process that we adopt.

"These are examples where VAR could have had a benefit and intervened to help the referee on the day.

"We are trying not to disrupt the flow of the game but on these occasions, the judgement should have been that it was a clear and obvious error."

He added: "One of the really positive things about the first four match rounds has been the quality of on-field performances.

"All the referees have incorporated the things we need to do with VAR into their refereeing while still focusing on making real-time decisions."

Overall 227 incidents have been checked by VAR in the Premier League this season.