West Ham striker Sebastien Haller was denied a penalty for Tom Trybull’s attempted tackle in Norwich City’s 2-0 Premier League defeat last month - in the view of referees’ chief Mike Riley.
Trybull's second half challenge was one of four mistakes made by the video assistant referee system (VAR) rolled out for the new season, according to Riley. But there was no mention of Haller's ugly challenge on Christoph Zimmermann in the same game or an alleged elbow from Andriy Yarmolenko on Trybull that both went unpunished.
Daniel Farke was highly critical of the crucial decisions against his side when he conducted his post-match media interviews at the London Stadium.
Riley, a former referee and the managing director of the officials' body Professional Game Match Officials Limited (PGMOL) addressed attendees at a Premier League shareholders' meeting in central London on Thursday, according to PA.
Riley pinpointed two penalties which should have been awarded to Manchester City and West Ham, and a Newcastle goal which should have been ruled out for offside.
It is understood he told top-flight representatives Leicester midfielder Youri Tielemans should also have been sent off for his challenge on Bournemouth's Callum Wilson in a league match on August 31.
The decision not to award City a penalty, when David Silva was tripped in the box by Bournemouth's Jefferson Lerma on August 25, was judged to be an error, as was the failure to give a spot-kick to Haller when he was upended by Trybull in the Canaries' match on August 31.
While Fabian Schar's goal for Newcastle against Watford over the same weekend should have been ruled out for a handball by Isaac Hayden in the build-up.
Riley told Sky Sports News that in the Silva, Haller and Tielemans incidents it was indicative of the high bar the Premier League has set for overturning the decisions of the on-field referee, but that he felt the 'clear and obvious' bar had been reached in each of these cases.
"If you look at the four match rounds 227 incidents have been checked," he said. "Out of that we've changed six decisions, (and) we think we should have changed 10 in total.
"That gives you the scale of where VAR can help and add value to the game. But it also demonstrates that this is still about refereeing a game of Premier League football on the pitch.
"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. These are examples were VAR could have had a benefit and intervened to help the referee on the day."
When pressed on why those mistakes were made, Riley said: "A combination of factors. That is the fascinating thing as this project evolves, we are constantly learning.
"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.
"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."
Farke was convinced his side were hard done by against the Hammers.
"I am not sitting here demanding red cards but one thing is for sure, there was a tackle against my centre back and the ball was three yards away. There was no red card, no yellow card, not even a free kick," he said, immediately after the 2-0 defeat. "Then two minutes later we were not able to substitute him.
"They counter, my centre back is not able to sprint back and he is one yard too late to block the cross and the player who made the tackle when the ball was three yards away rewards himself. It changes the whole game.
"You can speak about the 2-0, but there was a first half incident with the player who scored when my player was elbowed. The referee even spoke to him and his captain and warned him but he did not react again in this manner. This player scores the second goal.
"So VAR is probably not allowed to over-rule the referee but this demonstrates VAR is not always able to bring the perfect outcome. And I like VAR."
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