Manchester City boss Pep Guardiola has said the use of the video assistant referee (VAR) changes the "dynamic" of games after his side's 5-0 victory over West Ham on Saturday, where striker Gabriel Jesus became the first player in Premier League history to have a goal retrospectively disallowed.
Already 2-0 ahead, Jesus thought he'd scored a third for City -- only for Mike Dean to disallow the goal for offside following a consultation with VAR.
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This is the first season the technology has been used in the Premier League and VAR came into play again later on in the match, when Sergio Aguero's saved penalty had to be retaken due to encroachment.
"You have to be mentally strong when VAR is not on our side," Guardiola told BT Sport. "You think at 3-0 the game is almost over but at 2-0, the game is completely different.
"You have to be calm and be strong. It is going to change the dynamic not just for the team but for the spectators. It will be a good lesson for our future."
VAR played a part in City's exit from last season's Champions League, with the decision system disallowing a last-minute Sterling winner in their quarterfinal defeat to Tottenham.
"After what happened against Tottenham in the Champions League -- the passion, now we can control that emotion," Guardiola said. "It's good mentally, you have to be strong, have to learn to control our emotions."
However, despite seeing his side fall to a heavy defeat, West Ham boss Manuel Pellegrini said the use of VAR was beneficial to Saturday's game.
"I think it is fair for both teams in the way we use it," he said.
"This was a goal that was offside and for the penalty they decide it must be taken again. It will improve the fairer result of games."