Manchester United’s defence hasn’t looked great of late. Mourinho’s men conceded two against Sevilla to crash out of the Champions League, another two against Premier League strugglers Crystal Palace and have also shipped goals to the likes of Burnley and Bristol City this campaign.
Eric Bailly has returned in central defence to shore things up to a degree, but if Manchester United are to challenge for major honours next season and compete with noisy neighbours Manchester City then Mourinho will likely insist on defensive reinforcements.
But who does he want, and who could be available?
1 Raphael Varane
Manchester United are reportedly considering a mammoth bid worth £50 million for Real Madrid defender Raphael Varane, according to the Mirror.
The classy 24-year-old Frenchman has 40 international caps and 246 career appearances in all competitions to his name.
Varane has won La Liga twice, the Copa del Rey once, the Supercopa de Espana twice, alongside three Champions Leagues titles, three Super Cups and three Club World Cups during his time in Spain.
If Los Blancos manager Zinedine Zidane departs the Santiago Bernabeu in the summer then Varane may be deemed surplus to requirements by the unpredictable Madrid hierarchy due to injury problems.
There's no doubting Varane would strengthen Mourinho's defence after a pretty mediocre season for the Red Devils.
Mourinho is an admirer of the Frenchman, having tried to sign Varane in 2014 at Chelsea but was thwarted in his efforts to bring the centre back to Stamford Bridge.
2 Toby Alderweireld
Toby Alderweireld has faced a battle to regain his starting place in the Tottenham 11, due to the Belgian’s recent injury-enforced absence. This has caused manager Mauricio Pochettino to take to Davinson Sanchez’s partnership with Jan Vertonghen.
Alderweireld’s new contract talks have reached a dead end, with the 6 foot 2 defender reportedly demanding a £40,000 per week improvement on Tottenham’s initial offer. Rumours continue to circulate suggesting the central defender has now become a disposable asset.
Owing to a contractual clause, Antwerp-born Alderweireld can be bought for £25 million in the summer of 2019, a price tag which has alerted a host of top European clubs to the 28-year-old’s availability. This includes Real Madrid, Manchester United, Chelsea, Paris Saint-Germain and Manchester City.
3 Samuel Umtiti
United could swoop for Barcelona defender Samuel Umtiti with the Frenchman reportedly forced to delay extending his contract with the La Liga leaders.
Catalan bosses must wait until July 1 so they don't fall foul of UEFA's Financial Fair Play laws, after splashing out £145million on Philippe Coutinho in January.
The fact Barca's hands are tied at the moment could alert Mourinho into bidding for the Cameroon-born defender
Umtiti, 24, has a £53.4million release clause in his current deal which expires in the summer of 2021, making things very interesting.
Boasting both Copa del Rey and Supercopa de Espana titles to his name, the Frenchman would slot into Manchester United's defence with ease and is still extremely young, making his transfer a sound investment.
4 Danny Rose
The 27-year-old Danny Rose has been a star performer for Tottenham in recent years, but has slipped behind Ben Davies following injury.
United have repeatedly been monitoring Rose for a while, with Mourinho reportedly keen on a move.
Rose also fuelled further speculation of a move when revealing he has plans to move back north.
"I will play up north. I don’t know exactly when, but I will get back up north and play some football somewhere. I moved away from home [from Leeds to Spurs] at 16," Rose told The Sun.
Perhaps a possible swap-deal would suit both parties, with Tottenham one of many clubs linked with a move for out of favour Luke Shaw.
5 Jamaal Lascelles
Possibly the least glamourous out of the five picks, but at just 24, Lascelles is Newcastle's captain and has been their standout player this season.
Regularly proving to be Mr Dependable for the North-East side, he is also highly rated by his coach Rafael Benitez, and is in with an outside shot of making England's World Cup squad.
The Derby-born defender has shown great leadership quality, has an immense physical presence as well as an adeptness with the ball at his feet.
Mourinho will have to act fast however, as Chelsea are reportedly lining up the former Nottingham Forest man as a replacement for the ageing and out of favour Gary Cahill.
Let us know who you think Manchester United should sign in the comments section below.
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