Transfer news: Why Man United and Liverpool want £63m Sporting star Nuno Mendes

Sporting Lisbon have produced some wonderful attackers over the years - Cristiano Ronaldo and Bruno Fernandes to name a few - but Nuno Mendes may be the best defender to ever come out of their academy.

According to reports in Portugal, several of Europe's elite clubs are monitoring the 18-year-old left back's situation in Lisbon, including Liverpool, Manchester United, AC Milan and Juventus.

It would take the activation of his sizeable £63million release to prise Mendes away from the Portuguese club, so just why is the teenage defender so highly rated?

Sportsmail analyses exactly why Mendes is being tracked by some of the continents' best clubs...

Who is he?

Mendes is the latest of several wonderkids to come to prominence at Sporting Lisbon. Their academy has a rich reputation of producing some of the world's stars of the future.

Along with Portuguese legends Ronaldo and Fernandes, the Lions have brought through the likes of Luis Figo, Simao, Nani and Joao Moutinho.

The current crop of Sporting stars contain several highly-rated youngsters who have been linked to top clubs, including Joelson Fernandes, Tiago Tomas and defender Eduardo Quaresma.

After being scouted by Portuguese giants Benfica and FC Porto, Mendes joined the Sporting academy at the age of 10 and eventually moved into the club's live-in academy grounds when he turned 14.

Sporting's youth coaches could not decide whether he was best suited as a No 10 or a left wing-back, but by the time he broke into the club's first-team it was decided that he would begin his career as a defender.

In terms of his first-team breakthrough, Mendes was actually grateful for the beginning of the coronavirus pandemic last season as the cancellation of youth football meant he was one of several Sporting teenagers to be bumped up to the first-team.

Sporting head coach Ruben Amorim took no time at all promoting the teenager to the starting line-up with Mendes making his professional debut in the club's second game back after the Covid-19 hiatus and he has featured in almost every game since.

Overall, Mendes has made 34 appearances in all competitions for Sporting, scoring once and making two assists.

What are his strengths?

Mendes is a very attack-minded defender and has played the majority of his matches for Sporting as a left wing-back.

That means the teenager is very skilled in his close control and pressing going forwards.

Sporting's youth coaches noticed that Mendes' technique was of a very high level - hence the dilemma they faced over whether he should be an attacking midfielder or a left wing-back.

Mendes' youth coach Diego Goncalves told Record last year: 'We always started training with the 'ball-hunter'. We gave six or seven balls to 14 kids and they tried to get the ball off of each other.

'The exercise ended when Nuno was without the ball, which usually took around 15 minutes. Just to see the quality he had - it was outstanding.'

Mendes also has a few tricks up his sleeve, which comes from his background of being a street footballer in the Lisbon suburbs.

His school teacher Bruno Botelho once said: 'We did a one-on-one exercise against the goalkeeper to see where he was strong.

'Nuno lifted the ball over the goalkeeper with a rainbow flick, and scored with a no-look finish like Ronaldinho used to do.'

The close control and clever finishing was clear to see when Mendes scored his first and only professional goal for Sporting on the second day of the Portuguese league season back in October.

The teenager chased down a loose touch from Portimonense midfielder Koki Anzai, skipped past defender Mauricio Antonio with a clever touch, before finishing low past the goalkeeper following a sumptuous flick to create space inside the box.

Who is interested in him?

Liverpool are one of the sides who have reportedly held an interest in Mendes for quite some time.

According to Portuguese news outlet A Bola, Mendes was the subject of a £19m offer from Jurgen Klopp's Reds last summer, but Sporting wanted nothing less than his £40m release clause at the time.

Mendes has since signed a new contract with the Portuguese side to take that release clause above the £60m mark, but the defender has gained even more interest since then.

Manchester United and Man City are the other English clubs said to be targeting a move for Mendes, while AC Milan and Juventus have recently joined the pack.

Given Sporting held out for £67m to sell Fernandes to United back in January, the Portuguese giants would have no issues in holding out for their desired asking price should the big clubs make a move.

What are the chances of a move to England?

If Mendes was to pick the Premier League as his next destination, as Ronaldo and Fernandes did before him, then Liverpool appears to be the most likely option.

Not only have Klopp's Reds already signalled their interest in him with a reported transfer fee, but the Merseysiders appear to have the space to accommodate the signing of Mendes compared to Man United and Man City.

Liverpool have Andy Robertson as their first-choice left back but Kostas Tsimikas has struggled with injuries since his summer arrival from Olympiacos and has played just five times all season as the understudy.

Mendes would not only be an upgrade on the Greek defender but he would provide Klopp with a more solid rotation option should Robertson need a rest.

Ole Gunnar Solskjaer's United, meanwhile, are currently revelling in the recent performances of Luke Shaw at left back, while £15m summer signing Alex Telles is a solid back-up and rotation option having come from the Portuguese league himself with FC Porto.

A slight concern for both Liverpool and United would be Mendes' lack of experience in a back four, which both teams have adopted under managers Klopp and Solskjaer.

That could be an advantage for Juventus, who have rotated regularly between a back three and a back four under Andrea Pirlo this season.

The Old Lady have Alex Sandro at the club but the Brazilian has mostly been used as a left centre back, leaving the inexperienced Gianluca Frabotta, right-sided defender Danilo and winger Federico Bernadeschi as options on the left.

AC Milan have mostly used a back four this season and could do with some competition for current first-choice Theo Hernandez, who only has on-loan Manchester United defender Diogo Dalot as a left back rival.

Wherever Mendes ends up come the end of the season, the eyes of Europe will be on him for at least the next decade.