Real Madrid agreed to pay Porto €50million for defender Eder Militao on Thursday, meaning the Brazil international is the latest in a long list of players to break through at the Dragao and bring in a hefty transfer fee.

A number of clubs around Europe have forged reputations for their ability to sign players on the cheap, develop their talents and sell them on for huge profits.

Benfica, Sevilla and Southampton have all drawn acclaim for such an approach, but it is difficult to argue against Porto being the masters.

Militao, 21, only arrived in August for an initial figure reported to be around €4m from Sao Paulo, and yet he will leave as their biggest ever sale.

WHO IS REAL MADRID'S NEW SIGNING EDER MILITAO?

Below, we examine the other entries in Porto's top 10 biggest outbound transfers…

James Rodriguez – Monaco, €45m

Plucked from the relative obscurity of Banfield in Argentina, James really made a name for himself at Porto, resulting in Monaco flexing their financial muscle and bringing him to Ligue 1, where he continued to excel. An impressive 2014 World Cup with Colombia saw Real Madrid come calling, but things never quite worked out at the Santiago Bernabeu, and he has been hit and miss during a two-season loan at Bayern Munich.

Hulk – Zenit, €40m

Renowned as much for his likeness to Lou Ferrigno – who depicted the title character in the Incredible Hulk TV series – as he is for his footballing ability, the powerful forward took the road less travelled when joining Porto from Japan's Tokyo Verde. His cannon of a left foot proved a fine addition in Portugal, as he won a host of titles including the 2010-11 Europa League. Zenit came calling in 2012, and he has since moved on to Shanghai SIPG, who made him one of the world's highest-paid players.

Radamel Falcao – Atletico Madrid, €40m

Although not exactly prolific previously at River Plate, Falcao took to European football impressively, scoring 41 goals in 51 Primeira Liga appearances before leaving for Atletico in 2011. In LaLiga he remained lethal, but a move to Monaco was followed by dire loan spells with Manchester United and Chelsea after a serious knee injury. He has since rediscovered his form in Ligue 1, scoring 51 times since the start of 2016-17.

Andre Silva – AC Milan, €38m

Portugal's next great attacking hope, Silva had just one full season – netting 16 league goals in that campaign – in Porto's first team before Milan paid €38m for him. He struggled badly in Serie A, however, scoring just twice in 24 league games and was subsequently loaned to Sevilla. With nine strikes from 25 LaLiga outings, it looks somewhat unlikely they will be triggering their €35m purchase option.

Jackson Martinez – Atletico Madrid, €37m

A harsh reminder that the grass is not always greener. Martinez's career nosedived after leaving Porto for Atletico in 2015, having scored 67 in 90 league games in Portugal. He was unable to adapt to life under Diego Simeone, like many other strikers, finding himself sold to Guangzhou Evergrande seven months later. Injuries ruined his time in China, but, back in Portugal again with Portimonense, he is showing signs of his old self in the Algarve.

Anderson – Manchester United, €32m 

Dubbed the ‘new Ronaldinho’ for his silky footwork and the fact he came through the same academy at Gremio, Anderson looked destined to have a marvellous career early on. A broken leg disrupted him at Porto, but that did not put United off and they parted with a whopping €32m to bring the 19-year-old to Old Trafford. He certainly had his moments and was a crowd favourite, but he was converted into a deep-lying midfielder and he struggled for consistency, often impressing in big games before looking sluggish against lesser opposition. Injuries and fitness problems have blighted his entire career and he now plays in the Turkish second tier. 

Danilo – Real Madrid, €31.5m 

Part of the revered Santos team that included Neymar, Ganso and Alex Sandro – among others – and won the 2011 Copa Libertadores, Danilo's reputation went from strength to strength at Porto, becoming a regular in the Brazil squad. He impressed so much in an attack-minded right-back role that Madrid made their move in 2015, though he never truly convinced there. Now at Manchester City, he is a dependable rotation option. 

Eliaquim Mangala – Manchester City, €30m 

During his three-year Porto spell, Mangala became one of Europe’s most sought-after centre-backs. City won the race to sign him, earning the Dragons a cool €30m, but he rarely looked the domineering presence he had been in Portugal once playing in the Premier League. A loan to Valencia failed to bring much of an improvement, as they finished 12th in LaLiga. He is expected to leave City – for whom he has not featured since January 2018 – at the end of the season.

Pepe – Real Madrid, €30m 

After impressing early in his career with Maritimo, Pepe became a key player at Porto and showed promise with his physicality, leadership and willingness to scrap. His first few years in Madrid were disrupted by injuries and doubts about his quality, but in the 2010-11 campaign he really established himself and never looked back, going on to win every major honour with Madrid – including three Champions League crowns – and becoming something of a club icon. Now 36, he is back at Porto having left financially troubled Besiktas in January.