A midfield switch
Christian Eriksen started as a false nine in the first league meeting between these teams, was a deep-lying playmaker in the FA Cup semi-final, but was an unused subsitute last night.
It’s been brilliant to have him back, but it says a lot that Erik ten Hag wasn't going to play him just because he is fit, a mistake they have probably been guilty of in the past.
Eriksen had a poor game when the sides met at Wembley, so Fred was selected ahead of him in order to bring energy against one of the meanest midfields in the Premier League.
Read more: United player ratings vs Brighton
The United manager said it was 'the perfect game' for Fred given their need to press the Brighton midfield, but his performance was far from flawless.
Brighton were brilliant throughout and expertly cut through a United midfield that lost it's grip on the game. The intensity of the match might have been too much for Eriksen so soon after his return, but it was a reminder of the need for a more fitting alternative to him.
Martial misfiring
It's tedious to once again state United's need for a striker this summer, but this was their latest glaring reminder that an improvement in attack is desperately needed.
Anthony Martial started on the bench for the previous two matches and was fortunate to get a promotion back to the starting line-up for their trip to Brighton.
The Frenchman has always had the promise of more to come, but the harsh reality is that he has stagnated for so long and has clearly lost the intensity that used to make him so dangerous.
He is at best a squad player for a team at United's level and simply can't be relied upon on a regular basis like a top striker of the quality Ten Hag wants to sign.
They should have moved on from him a long time ago. This summer there can be no excuses.
A moment of madness
Luke Shaw was United's best player when these two sides met at Wembley and he was their best player again for 95 minutes last night.
The game changed when he conceded a needless free-kick in the dying embers of the match, and it got even worse when he needlessly handled in the box to give the hosts a penalty moments later.
These are the fine margins that so often define the games at the very top level; they are the moments where United still so often fall short.
It is by no means on Shaw's shoulders alone, but he is the one who will need to step up and be counted in response.
The £80m transfer regret
When you mention the words £80m transfer regret, the initial reaction is to think of Harry Maguire. It can apply to Moises Caicedo as well.
As we approach a summer in which United will look to sign another top midfielder, they must be ruing the missed opportunity of passing on Caicedo.
The club were looking at him back in January 2021, but opted against a move for a then-unproven youngster, partly down to agent fees' involved and an overall uncertainty regarding who actually represented him.
Brighton were in a better position to take such a gamble, and it is one that has highly paid-off. The 21-year-old scored against United last season, bossed them on the opening day and was man of the match in the FA Cup semi-final last month.
He can now add another masterclass against them to that list, with an incredible performance on Thursday night that saw him play as a right-back out of possession and tuck into midfield whenever his side got the ball.
It could take around £80m to sign him when he does eventually leave the club, though based on his most recent outing, his versatlity could bring it closer to £100m.
United record highlights how big their underlying problem is
It's so difficult to evaluate just how successful Ten Hag's first season at United has been when they are such a different beast away from home.
United have been formidable at fortress Old Trafford throughout the campaign, but have come unstuck time and time again on the road against the best teams.
They have now taken just one point from their away matches against the top nine sides in the Premier League, with that coming a week ago against Tottenham.
They lost away to Man City, Arsenal, Newcastle, Liverpool, Tottenham, Brentford and now Brighton. There are clearly bigger problems to solve than Shaw's silly handball.
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