Manchester United defensive frailties - is Jose Mourinho right to worry?

Manchester United's defence came under fierce criticism after their 3-2 defeat at Brighton on Sunday - but just how bad is the United backline, and would their missed targets have improved things?

Much has been made of the evident friction between Jose Mourinho and the United hierarchy after a disappointing summer in the transfer market. Mourinho earmarked a central defensive signing as priority, but as the window slammed shut no new central defensive addition came in, leaving Mourinho insisting it will be "really hard" for United to finish in the top four.

"You can't three quarters build a house and then stop," Gary Neville said of United's lack of investment. "That back four [against Brighton] is not good enough to win the Premier League title."

Is Neville right to be so critical of United's back four? What is the solution to their rearguard woes? Are the defenders solely to blame? We take a look...

United defenders perform well, just not as well as Maguire

Statistically, Manchester United's defenders did not fare too badly last season. Only three defenders made more interceptions than Chris Smalling, Antonio Valencia ranked in the top ten for ball recoveries, while Phil Jones and Victor Lindelof were two of the top six most accurate passers to have played more than 10 games.

However, Harry Maguire's stats won't appease United fans disappointed the England international was not brought in.

For players who played more than 10 games, Maguire recovered 17 more balls than anyone else in the division last season, finished with the highest number duels won, in the top ten for blocks made, as well as ranking higher than any United defender for aerial duels won and clearances.

Mourinho, though, will not highlight these stats to back his claims, as Maguire was not his preference. Instead, Mourinho wanted more tried and tested reinforcements, with Toby Alderweireld reported to be a target.

The United board were reluctant to spend big on a 29-year-old, and have some justification for doing so, after the Belgium international did not enjoy the best of seasons last time out.

Injury problems and a fall-out with Mauricio Pochettino did not help matters, but per 90 minutes, of players to play more than 10 league games last season, Alderweireld made the fewest number of interceptions of any defender in the Premier League, while only two defenders won fewer duels per 90 minutes.

Who is the best partnership? Or is three at the back the answer?

On Sunday's evidence, it does not seem Victor Lindelof and Eric Bailly, both bought by Mourinho for around £65m combined, are the answer.

The opening games of this season are the only two games the pair have been deployed as United's centre-back pairing, and after four goals conceded against Leicester and Brighton, Mourinho will be considering a change for Monday's clash with Tottenham.

The Portuguese has chopped and changed his central defensive partnerships regularly since taking charge but, as Sky Sports' Jamie Redknapp alluded to at the Amex on Sunday, seems no closer to working out what his strongest side is, especially defensively.

Jones and Smalling are the most common partnership utilised by Mourinho from throughout his tenure, but with limited success, having accrued just a 46.1 per cent win ratio when together in the heart of United's defence.

The most successful partnership is a Jones-Bailly axis, with United having emerged victorious in eight out of nine league games the pair have started at the heart of the backline together. Injury problems for both, though, have limited the opportunity for the pair to develop a regular partnership.

With those injury problems in mind, and Mourinho's uncertainty on which pair he prefers, Neville had an idea as to how best to solidify United.

"I think it [Brighton defeat] will force Manchester United and Jose Mourinho to go three at the back," he said on the Gary Neville Podcast. "I think, with the centre-backs he's got, he will resort to that.

"When I look at the centre-back partnerships that he had at Chelsea, they had power and strength in his teams. He hasn't got that here yet."

Such a move has proven relatively successful in the past for Mourinho, having seen his United team lose once from six when deploying three at the back. Mourinho in fact experimented with three at the back in pre-season against Real Madrid, seeing his side beat the European champions 2-1.

"Because with three they can support each other a bit more," Mourinho said when asked why he chose such a system. It could, with Mourinho lacking confidence in his defensive options currently, be the arch-pragmatist's best option going forward.

Do United's problems in fact lie further forward?

It does seem somewhat churlish to suggest United are vastly inferior at the back, when they shipped just 28 league goals last season, only one more than champions Manchester City. It was the fact that four teams scored more league goals that proved costly.

The front six at United did not provide much support at the other end, either. Take Nemanja Matic's excellent defensive stats out of the equation from last season, no other United midfielder ranked in the top 30 Premier League midfielders who played more than 10 games for interceptions, ball recoveries, clearances, blocks and tackles won.

That lack of protection ahead of the back four continued at Brighton on Sunday. United's entire midfield, including substitute Marouane Fellaini, made just two tackles at the Amex. Brighton's Davy Propper alone made seven. United's defensive midfielders - Fred and Andreas Perreira - mustered just one clearance and two interceptions between them.

The defence is not excelling as well as a title challenger should, but Mourinho's problems defensively do not stop at the back four. There's much for the manager to ponder ahead of an already crucial clash with Tottenham on Monday Night Football.

Credit: Skysports.com