Mourinho mistakes: Failure to sign another centre-back and derby misery

After Manchester United had beaten Hull City 1-0 on Aug. 27 with Marcus Rashford's late winner making it four competitive wins from four in the Jose Mourinho era, the Portuguese was prepared to make a bold statement.

"Today they showed we want to be champions. We don't want to start well. We want to finish well," Mourinho said.

But United lost their next game 2-1 to Manchester City and since then, they haven't been right. They have only won one league match since the victory over Hull, the 4-1 thrashing of Leicester City on Sept. 24. Even that win over the champions didn't fix the team's issues in the way that had been anticipated. The stop-start nature of United's season has instead been reminiscent of Chelsea 2015-16 in the way every positive has been followed by a negative.

While it would have been unreasonable to expect Mourinho to proceed problem-free, that's not to say the other extreme was expected. United have gone from a side who looked like they had some of their old aura back, to a team playing under a manager who seems to be suffering.

How did it get to this? Here's a look at the reasons behind Mourinho's troubles:

Failure to sign another centre-half

It is something that is going to be further exposed after Eric Bailly's injury in the 4-0 defeat to Chelsea, but also became apparent in the game itself. Bailly has impressed since his £30 million arrival from Villarreal but he is inexperienced and prone to the odd mistake. Mourinho doesn't have the experienced defensive leader he has always valued in his teams.

The club inquired about Juventus' Leonardo Bonucci when negotiating for Paul Pogba, but the price would have been too high in a summer where they had spent around £150m. Southampton's Jose Fonte emerged as a cut-price alternative, but United wanted to sell before they bought. That didn't happen and the defence has often lacked composure, however promising Bailly has been.

The first half of the first derby

United may have recovered in the second half to only lose 2-1 to City on Sept. 10 but that didn't cover the concerns over how wide the gap between Mourinho's side and Pep Guardiola's in the first half.

City went into a 2-0 lead but on the basis of how dominant they were and how easy they found the match, it so often had the feel of utter humiliation. Since Mourinho's problems started in that game, it's difficult not to think it caused a loss of confidence and sapped some of their momentum. United have rarely been the same since. Rather than spurring the squad on to hit back after defeat, it only seemed to remind everyone of how much work they had to do.

The way they were beaten against Watford

It was not that United suffered a second successive league defeat, and third in all competitions, to compound their issues. It was about how the 3-1 defeat at Watford eight days after the derby defeat was down to such a simple breakdown in the basic things Mourinho sides usually guarantee -- and the manager's response to them.

After Watford scored two goals through the same type of attack out wide, the Portuguese publicly castigated Luke Shaw. The player has acknowledged the need to improve and although the squad were initially struck by how hard Mourinho had been, sources say any shock has passed. Such a tactic can only be used sparingly for it to have real power, and the Portuguese went to it very quickly. It stopped working at Chelsea last season.

Of course, the way to prevent its necessity is to get the team functioning properly, but nobody has seen that yet. The defence is still patched together. The attack has been one-dimensional. Watford realised Mourinho's team can be tactically outmanoeuvred.

Stoke's equaliser at Old Trafford

As poor as United have been in attack in the last two league games, it should not be forgotten the first half display against Stoke City was as good as anything they have produced this season. The forwards linked up well and threatened to overwhelm Mark Hughes' side, but couldn't find the finish and then ran out of steam.

When teams like United are on one of these inconsistent runs where almost every game feels borderline, you need moments to go your way, to generate a sense of momentum; to foster the idea that what you're doing is correct. It didn't go United's way. The defence suffered the kind of calamity that comes when a backline isn't properly cohesive and Joe Allen scored a fortuitous equaliser. The zip was gone from the players. The attackers went back to high punts and crosses because they no longer had the confidence to cover Mourinho's lack of attacking planning.

It all added up in that match against Chelsea. The defence fell apart and the attack couldn't produce a response. By the end, N'Golo Kante was coursing through a fragile side to make it 4-0, completing Mourinho's humiliation.

Miguel Delaney covers the Premier League and Champions League for ESPN FC. Twitter: @MiguelDelaney.