LONDON • Jose Mourinho said that the use of the video assistant referee (VAR) to disallow a Juan Mata goal in Manchester United's 2-0 FA Cup fifth-round win over Hudderfield Town "went against the original protocol" of the system and that football is "too beautiful to be spoiled by something not perfect".

Mata was initially adjudged to have beaten the offside trap to score in the first half, but the decision was referred to VAR and he was deemed to be beyond the last man - or, at least, his knee was slightly beyond the offside line.

However, shots from VAR showed uneven, wavy lines drawn across the picture, making a mockery of the system.

When straight lines were eventually put on the shot, it showed Mata's kneecap to be offside, but questions will be raised about whether that was the correct circumstance for it to be deployed, as it was not a clear and obvious error.

The managers at the John Smith's Stadium were both unhappy with events in different ways.

For Mourinho, it was his first live experience of VAR, though he is familiar with the system from its use in Portugal.

"It has thrown up some amazing results, but there have also been problems and frustrations," he said.

"It is not reliable yet and I think the game is too beautiful to be spoiled by something not perfect.

"I also believe the way the system was used at Huddersfield went against the original protocol, which was specifically to correct clear and obvious mistakes. It takes a long time too, and then you have to cope with the frustration if the decision goes against you."

Thankfully for United - and the authorities - that decision did not have a definitive influence on the outcome, as Romelu Lukaku struck early in both halves to take his tally for the season to 21.

David Wagner might have been the beneficiary of VAR on this occasion but he remains sceptical.

"I don't like it, I never have," the Huddersfield coach said.

"Maybe I'm too traditional, but it kills the emotion in the stadium, and for me that's a big part of football's attraction."

The controversy took some of the spotlight off Paul Pogba's absence after a week of rumours concerning his Old Trafford future.

He had failed to travel for the tie, reporting sick on the morning of the game and leading United to take the highly unusual step of making an official announcement that he would be unavailable due to illness.

The midfielder, who returned to United from Juventus for a then world record £89 million (S$163 million) in 2016, has not completed 90 minutes since a 1-0 win at Burnley just under a month ago.

Mourinho angrily insisted on Friday that speculation about his relationship with Pogba has broken down were "lies and bull****".

But, when asked about the absence of Pogba and others against Huddersfield, Mourinho seemed to allude to the France midfielder's flamboyant lifestyle.

"We had some players missing, but we had some players that played and played so, so well," he told MUTV. "Honestly, I think Scott (McTominay) deserves more than what he is getting.

"I think maybe it's because he's this kind of kid profile: a normal haircut, no tattoos, no big cars, no big watches, humble kid, arrived in the club when he was nine or 10."

It remains uncertain if Pogba will be fit to face Sevilla in their Champions League last-16 first leg on Wednesday.

THE GUARDIAN, AGENCE FRANCE-PRESSE