The defeat in the Amex stadium felt like the culmination of a number of problems that Manchester United had threatened at the start of the Premier League season 2018/19.
Jose Mourinho's failure to sign a central defender prior to the transfer deadline has led to criticism of the way Ed Woodward tackles the summer window, while others think the Portuguese can not get the most out of a team pick up that has been left for some time.
The players are also not acquitted of guilt. There is a school of thought that Mourinho has put trust in a number of individuals who have not repaid him.
From above United comes under attack again because rivals Liverpool and Manchester City are ready for a battle for the title of the Premier League.
So who is actually responsible for the current situation at United?
Who is not the culprit of United? Jose Mourinho has spent more than £ 370 million since the takeover, but this was the summer for United to beat City and really continue if they wanted to be serious about ending their title drought.
Doing business is good when it comes to the commercial prospects of the club, but Woodward did not give Jose Mourinho the support he expected after signing a contract extension earlier this year.
Fred is the only new starter to arrive so it is Mourinho's job to get so much more out of Alexis Sanchez, Paul Pogba et al and he should be.
Let's not forget that Woodward has already delivered a few £ 30m middle ridges in Victor Lindelof and Eric Bailly.
But the players must also take their share of the debt.
Paul Pogba admitted after the game that his stance was not correct against Brighton, worrying, especially when United received so many lessons from teams that fought for their lives in the last 12 months.
You just worry about the general direction of the club when the Glazer main point is to qualify for the Champions League every season. That does not show signs of changing quickly.
Without having to avoid answering the question directly, the reality is that you can not just point an accusing finger at one person.
Look at the Brighton game, it's easy to blame Jose Mourinho. The way United played it looked like they did not have a game plan or strategy.
As soon as the first goal was lost, the players seemed to have no idea what they were doing. But it raises the question what they do in the training.
It is hard to believe that they did not go to that game with a strict game plan. Whether it is a game plan that the fans wanted to see or not, there is no way that Mourinho did not set up his team to go out and win.
Each player on that field dropped the team in the Amex Stadium. Game plan or not, they did not have the fight or the wish to win and Paul Pogba summarized this in his interview after the game.
And all that is without affecting the influence that the Glazers and Ed Woodward have had at the club over the years.
Everyone has contributed to helping United to enter the chaos they are currently in.
Can I tell everyone? Ed Woodward has provided the vast majority of José Mourinho's transfer targets since the arrival of the Portuguese in Old Trafford in 2016, but did not support him in his search for a defender this summer.
Woodward handed Mourinho a new contract in January, so it made little sense to not pursue all his goals during the transfer window.
That said, the two backsupport that started in the bitter defeat of Brighton – Eric Bailly and Victor Lindelof – were both great Mourinho signing sessions and it is clear that he is not getting the best out of his players.
United were wildly disorganized at the back of the south coast and there is no clear plan for an attack.
Mourinho must take most of the blame for United's tedious style of playing, but the attitude of some players at the Amex was wrong.
The lack of leadership within the team was clear and Paul Pogba's comments after the game were outrageous. We are only two games in the season, but United will be in a crisis if they lose Spurs on Monday.
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