Louis van Gaal has suggested that Manchester United should have had a penalty in Saturday's 1-0 defeat at Chelsea.
Eden Hazard struck the only goal of the game as the Blues moved ro within two victories of the Premier League title.
There was a contentious moment in the dying seconds when referee Mike Dean booked Ander Herrera for simulation following a challenge with Gary Cahill, but Van Gaal has hinted that he feels otherwise.
"I am not frustrated, I am proud. Why should I be frustrated? We played the best match of the season," he told BBC Sport.
"In my opinion that is the main decision of the referee [when Herrera was booked]. Maybe you can watch the replays on television."
United stay third in the table, 11 points behind the Blues having played one game more than them.
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