Bruno Fernandes had a penalty saved as Manchester United fell to a 3-1 defeat at Brentford to put the spotlight back on Ruben Amorim as his search for back-to-back league wins continues.

United were 2-1 down as Fernandes waited more than four minutes to take his second-half spot-kick which was eventually saved by Caoimhin Kelleher after VAR checked if Nathan Collins should have been sent off for denying Bryan Mbeumo a goalscoring opportunity.

Referee Craig Pawson's decision to book Collins was upheld, without him being sent to the monitor, despite the Brentford defender making no clear attempt to play the ball when pulling his former team-mate back by the shoulder.

United only have themselves to blame for the result, their third defeat in a four-game winless run at Brentford, that was sealed when Mathias Jensen struck a superb third goal in stoppage-time. All the momentum of the win over Chelsea had vanished.

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Brentford were two goals up after 20 minutes thanks to Igor Thaigo's first-half double and, although Benjamin Sesko scored his first goal for the club to halve the deficit six minutes later, United were never convincing in their fight-back.

Fernandes' second failure from the spot this season ultimately cost United, who are now winless in their last eight away league games and back in the bottom half as Brentford climb above them thanks to a richly deserved three points.

Amorim disagrees with officials on Collins

Amorim disagreed with the decision not to send off Collins but said his team should have done more to manage the game after Fernandes failed to convert his penalty.

"They told me Bryan was not in control of the ball. I think he was not in control of the ball because he was pulled," Amorim said in his post-match press conference.

He added: "Sometimes the decisions are not in your favour. We have the capacity to calm down the game. We didn't do that today."

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Former Premier League official Mike Dean, speaking on Soccer Saturday, was in agreement: "For me, it is a red card."

Sky Sports pundit Kris Boyd added: "It is another poor afternoon for Man United. They will be raging. Collins had to be sent off."

Andrews on winning midfield battle against Man Utd

Brentford changed from a back five to a back four against Amorim's three at the back system, but head coach Keith Andrews kept his midfield three of Jordan Henderson, Yehor Yarmoliuk and Mikkel Damsgaard.

Not for the first time this season, United's midfield pivot of Fernandes and Manuel Ugarte were outnumbered and overrun by Brentford.

Asked if he felt it was an area to target, Andrews said: "It's the natural way you prepare for games. You try and create overloads. One of which would be if we have a three-man midfield, they have a two. But you could flip it and say 'if their wide players tuck in then they have a four.

"But I certainly felt how we tried to entice them onto us and try and play around, or through, at times, would be on. And I felt, going back to it, the players did that with real courage and conviction."

On goalscorer Thiago, Andrews added: "He's getting real rhythm in his game now and confidence in his game. He's shown exactly why the football club brought him here. He's such a powerful player. Very positive individual and very selfless."

Man Utd lacklustre in defeat at Brentford

Winning two in a row used to mean something different at Old Trafford. They came to Brentford in search of the club's first back-to-back league wins under Amorim, but Thiago scored twice in the first 20 minutes before the United players had woken up.

Harry Maguire was culpable for the opener as Jordan Henderson's long ball over the top caught him napping. Thiago was all alone when he hammered in the opener. The whole stadium thought he was offside, only for replays to show Maguire was slow off the mark.

United, losers in every league game in which they have trailed this season, were unable to cope with Brentford, who terrorised their visitors from set-pieces. Altay Bayindir made two fine saves from Henderson and then Collins but was at fault for Thiago's second.

The Brentford striker just had to fire in from close-range after Kevin Schade's cross was spilled by Bayindir in the six-yard box. Thiago needed just six touches to score his two goals, which takes him to five in seven games this season.

This was the first time Amorim had started United's £207m front three of Mbeumo, Sesko and Matheus Cunha but the first impression was not a positive one. Their lack of desire to help in midfield left the pivot of Fernandes and Manuel Ugarte exposed.

Sesko did manage to break his United duck in his fourth start for the club as Patrick Dorgu's hopeful, looping cross eventually found him. It took three goes to beat Kelleher from close-range, the former Liverpool keeper pulling off a couple of fine saves.

Brentford taking their foot off the gas gave United encouragement, though they lacked punch. When the spot-kick was awarded it felt like the piece of luck that Amorim needed to turn his troubled tenure around, but Fernandes let him down.

There was no response from United as Brentford took further encouragement before adding a deserved third in stoppage-time through substitute Jensen. His swerving shot finished centrally to make Bayindir look foolish. He was not the only one.

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