Manuel Pellegrini thinks West Ham would have beaten Manchester United had VAR been in operation at Old Trafford on Saturday.
United benefitted from a hat-trick of debatable refereeing decisions on the way to a scarcely deserved 2-1 home victory in the Premier League.
Felipe Anderson had a goal erroneously disallowed for offside in the early exchanges, before Paul Pogba opened the scoring with a penalty following a Robert Snodgrass tackle on Juan Mata that Pellegrini argued was outside the box.
The Hammers equalised through the impressive Felipe Anderson after half-time but, having looked the more likely to snatch a winner, came undone via a second Pogba spot-kick in the 80th minute.
Ryan Fredericks brought down Anthony Martial from behind amid suggestions the Red Devils winger strayed beyond the last defender as he raced onto a throughball.
"It's hard to say how we have not come away from here not only with a point, but all three," Pellegrini said at a news conference.
"For me, it was a pleasure to see the way the team played here, against Manchester United at Old Trafford. It was a very good performance and we were unfortunate [not to get a result].
"I don't want to complain about the referee because all of them were very difficult decisions.
West Ham United (@WestHamUtd) April 13, 2019
"[Felipe Anderson's disallowed goal] was onside, by just one foot, so that's why the mistake was made. If we have VAR it's a goal.
"The second goal they scored was a mistake from us, but it was also offside. [Marcus] Rashford touches the ball, so it's offside.
"We also made a mistake for that goal and I'm not complaining that we lost because of the referee.
"The three of them were very difficult decisions. It was not possible to see, but with VAR we win this game."
The win for Manchester United kept the club within two points of the top four, while West Ham sit 11th following the loss.