In 2011, Manchester United set up with a team against Swansea in the Premier League that consisted of Ashley Young and Antonio Valencia on the wing, with Chris Smalling at centre back and Phil Jones at right back.

Wind forward six years and instead of Young and Valencia occupying the wing, they are now Manchester United's first choice left and right back, with Jones shifting inwards and creating a feeble partnership with Smalling.

While Valencia has been a useful asset more often than not for the Red Devils, it is astounding to think that this is the state of Manchester United's four-man defence six years into the future.

It has been alarming to see the lack of quality in Man United's squad, emphasised by Smalling's presence in the starting XI. José Mourinho might have spent a fortune already, but he, and the club, simply have to be ruthless this summer in clearing out the deadwood and recruiting smartly.

Here are the players that should be sold:

  • Chris Smalling 

Under Louis van Gaal, Smalling had a season which suggested that he could finally be maturing into a player of the required standard to represent Manchester United at the highest level.

Since then, however, the England international has regressed massively and turned from 'Mike' back into 'Chris'. It has been alarming to witness Smalling's performance level drop right through the floor.

What is interesting is Mourinho's approach to Smalling. The Portuguese boss has made it very clear that he prefers ball-playing centre backs, but the Man United defender is just not that. Instead, he looks like Bambi on ice when he receives the ball.

Time and time again, Smalling's route out of defence is a long hit-and-hope up to Romelu Lukaku. He is anything but a ball-playing defender and there is a reason why opposition strikers target him relentlessly when the ball comes to him - they know there's a mistake-in-waiting.

Smalling is a liability in defence and should be nowhere near the starting XI - Man United need better reinforcements to take his place.

  • Matteo Darmian 

For some reason or another, Darmian could not be further from the 'tradition Italian defender' that he was at Torino.

The Italian joined off the back of a very impressive World Cup in 2014, but after a good few months, Darmian has been utterly atrocious in both attacking and defending. He is shy to cross the halfway line and, if by some miracle he does, the Italian then struggles with what to do with the ball, let alone execute his decision.

Defensively, Darmian has been caught out by a number of attackers and is a rogue liability in defence. His positional awareness is non-existent and he doesn't pose a threat aerially, constantly being out-jumped and dominated.

Manchester United's right back options are currently very limited, with Valencia being the first choice and Ashley Young, a traditional left winger, being a back-up solution. Darmian, whenever he has played, is usually placed on the left as cover, but the performances stay at the same level of lacklustre.

  • Ashley Young 

While Young has been good in parts for the Red Devils this season, they simply cannot go another season with him being the first choice left back. Luke Shaw is in the process of renewing his contract at the club and should be trusted to
start week in, week out.

Young has done an incredible job in staying at Manchester United throughout the years of him underwhelming considerably, but, at 32, turning 33 this year, it is time to move on.

Especially with Young's reported £110,000 per-week wage, Manchester United need to act smarter in offering huge wages to players that don't deserve such a deal.

Shaw might have had a difficult time in the past 18 months, but there is nothing that Young offers that Shaw can't match or even better. The 22 year old still has time to correct his lost time at the club due to injury and is only on the edge of entering his prime years.

There needs to be an overhaul at United and the old regime must slowly be let go. Young might give all he can for the shirt, but that is just not good enough anymore.

  • Michael Carrick 

Manchester United would never sell a player of Carrick's outstanding quality, but the former England international has already confirmed that he is retiring at the end of the season.

With that being said, Manchester United will need to replace him and will have to find a player that can match his composure on the ball along with his professionalism. Carrick has been a role model to the younger generations coming through and has been a sensational servant to the club over the 12 years he's been at the club.

Julian Weigl, of Borussia Dortmund, and Jorginho, Napoli, will be two players high up on Mourinho's shortlist to replace Carrick. Both have mesmerising quality on the ball and would provide a similar role to that of the former Spurs man.

Manchester United will not stay in the shadow of their across-town rivals Man City, but they need to release the players that are not good enough while also bringing in around four players that are of a very good quality that can slot into the system accordingly. It's time for the Red Devils to become ruthless.

This article was written by Liam Canning for Soccer Box, an online football store where you can shop for the latest Manchester United football kit including personalised shirts for all your favourite players.