Koulibaly, Sancho & 5 players who Man United should sign to compete next season

Starting the 2018/19 campaign, Manchester United had signed a young Portuguese right-back in the form of Diogo Dalot from Porto and a midfielder to help out Pogba in the form of Fred from Shakhtar Donetsk. However Mourinho's need for a central defender wasn't completed and he entered the season with Lindelof, Bailly, Smalling, Jones and Rojo as his defenders.

Without a shadow of doubt, Manchester United have struggled at the back and are now on the lookout for a new defender to replace an injury-prone and rather inconsistent Eric Bailly and to get rid of either of Jones, Smalling or Rojo, with only Lindelof having shown promise of being a good defender of the lot.

Along with the defense, their midfield has struggled all season apart from Paul Pogba who, although inconsistent, has shown what he can do even with players under performing around him.

With players like Ander Herrera and Juan Mata looking to be leaving for a free in the summer, Ole has got a lot of work to be done with this squad and here are some of the players who he should target.

5. Aaron Wan-Bissaka

Aaron Wan-Bissaka has been a sensation this season for Crystal palace, donning the right-side of the Palace defense all on his own. The 21-year-old England international has made 149 tackles so far this season with a tackle success percentage of 68% which is amazing for a player so young.

He has also made 85 interceptions, 147 clearances and 221 recoveries -- the best for any other full-back this season. Although his attacking output has not been as impressive as fellow England international Trent Alexander-Arnold, it is something that can be improved if he plays for a side like Manchester United.

If United go for him, it is safe to say he is a significant upgrade over Ashley Young and can don the jersey for at least the coming decade.

4. Adrien Rabiot

Adrien Rabiot is all set to leave the Parisians for a free, come summer, after failed contract negotiations between the club and the player. Having been touted to be on his way to Barcelona, it is safe to say the ship has sailed after they signed Frenkie de Jong in January.

With Ander Herrera all set to leave the club in the summer to PSG as per reports, it will be a significant upgrade for the Manchester club if they could snap up the Frenchman for a free.

Rabiot is miles better than Herrera when it comes to defensive ability. Rabiot is dribbled past only 0.2 times per game compared to Herrera's 1.9, which is a massive difference.

With United's wage structure, it is more than capable for them to meet Rabiot's wage demands and also have a player who is better than Herrera in every way possible.

3. Wilfred Ndidi

Wilfred Ndidi has been exceptional for Leicester City this season as he has helped them out defensively a lot more than any other player in the Leicester team. He is second in the league for tackles behind Everton's Idrissa Gueye and has a very remarkable success rate of 70%.

With Leicester building a young squad with a very impressive midfield trio of Maddison, Tielemans and Ndidi, it may be hard to get the Nigerian international from the Foxes for cheap, but if they do manage, it will be a very good investment for Manchester United.

Still only 22, it may cost United upwards of £50 million to get him to the Theater of Dreams but given Nemanja Matic's current form, they can't afford to take risks with the Serbian slowing down pretty evidently and help shore up United's midfield which has been struggling off late.

2. Jadon Sancho

The teenage sensation who left Manchester City for Dortmund in search of playing time shows what talent City and Pep have missed out on. He has had a sensational season for Borussia Dortmund, helping them alongside Marco Reus and Paco Alcacer to put on a title challenge in what has been a long time.

He has scored 11 goals and assisted 14 more this season in the Bundesliga alone and has been dragging them through their rough patch when Reus along with other attackers were having a tough time.

Sancho is still only 19 and it will be very tough to lure him out of the German outfit. Also the fact that he was a former City player will be tough but the right price will surely bring him to United and make him one of their own.

1. Kalidou Koulibaly

Napoli's defensive stalwart has become a major target for many clubs in need of defensive reinforcement this season and rightly so. Koulibaly has been a rock at the back so far and he is having his best season of his playing career thus far.

He has made 1.7 tackles, 1.2 interceptions, 3.9 clearances and 1 block per 90 in all competitions and also has been dribbled past only 0.5 times this season. With United's squad sorely lacking in defense this season, he can cause an instant impact to this United squad. If he is utilized properly, he can be vital for them.

It may cost United a world record fee for Napoli to sell him but if he does join, he will be head and shoulders above every defender right now in the United squad and help them and De Gea, who has been suspect this season, gain his confidence back. He can be the defensive leader they have missed all these years.