Manchester United failed to build on the momentum of Thursday's late comeback against Southampton as they suffered a woeful defeat to Brighton at Old Trafford.

United conceded an early goal at home once again, with Yankuba Minteh scoring inside five minutes after good work from Kaoru Mitoma caught the hosts napping. Bruno Fernandes' penalty levelled things up before the break.

But a dismal second-half display condemned United to a sixth defeat in nine Premier League matches. Minteh returned the favour for Mitoma to score, before a dreadful Andre Onana blunder gave Georginio Rutter a tap-in. United never looked like getting back into the game after that.

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Onana blunder

The sound you heard when Andre Onana dropped a routine ball at the feet of Georginio Rutter was the air being sucked out of Old Trafford. Any chance of another United comeback went up in smoke with another error from an increasingly error-prone goalkeeper.

United fans are losing patience with Onana, who is producing blunders at an alarming rate. He was supposed to improve United's distribution but the sound of agitation when he has the ball and takes too long over a pass suggests that isn't happening either.

He is making too many mistakes to keep his place in this team. Altay Bayindir had his best game in a United shirt at Arsenal and is arguably deserving of a chance in the Premier League now. Either way, Amorim must surely be considering a change in the summer.

Subs show the problem

When Amorim turned to his bench for attacking reinforcements soon after his side went 3-1 down, he offered words of encouragement to Antony. For the second time in four days, the Brazilian was being asked to rescue a losing cause.

That he is being called upon to change games when his own time at the club is coming to an end shows how stretched and how weak this squad has become. Antony isn't good enough, is leaving the club, but is still needed.

With Marcus Rashford's United future also likely to be measured in days rather than months, it is clear Amorim needs attacking reinforcements before the transfer window closes on January 3.

Slow starts

Amorim tries to keep his cool when United score, but he can't always hide his emotions when they concede and he was visibly frustrated when Yankuba Minteh scored inside five minutes at Old Trafford.

It was the third time in the last five home games that United had conceded inside five minutes, against Nottingham Forest, Newcastle and now Brighton. Against Bournemouth and Southampton they conceded in the first half and in all five games they conceded the first goal.

That is a dismal record against five teams United really should be beating at home. It is a weakness Amorim is clearly getting agitated by and one that isn't the easiest to solve.

This time, it was the defence that was caught out. The line was all over the place when Carlos Baleba sent a ball over the top and Noussair Mazraoui was easily beaten by Mitoma. It was sloppy defensive play and it is happening early in games far too often.

Law tributes

It was a poignant and emotional day at Old Trafford, with tributes paid to Denis Law after his death in the week. The 84-year-old was the final member of the United Trinity, immortalised in a statue outside Old Trafford, to pass away, after George Best and Sir Bobby Charlton.

Once again, United got the tone of the tributes just right. Piper Terry Carr led the teams out, playing the Flower of Scotland, while the teams were joined on the pitch by Law's former teammates Paddy Crerand, Alex Stepney and Brian Kidd, as well as Law's friend Sir Alex Ferguson. The TV cameras caught the group sharing a laugh at the mouth of the tunnel before the teams came out.

A minute's applause followed and Law's was a life and a career well worth celebrating. The celebrations began with David Bowie's Heroes and then 'A drink, a drink, a drink for Denis the king, the king, the king' being played over the PA system.