As Man Utd have a £75m bid for Romelu Lukaku accepted, we pick out the best players Jose Mourinho originally deemed not good enough...
United boss Mourinho has enjoyed success across Europe since steering Porto to the Champions League trophy in 2004, winning league titles at Chelsea, Inter Milan and Real Madrid, but "the special one" has shown the door to a number of top-class players during that time.
Mourinho may have brought back the one that got away under Sir Alex Ferguson at Old Trafford in Paul Pogba, but now United have spent big money to try to re-sign Lukaku, a player who couldn't find a way into Mourinho's Chelsea team in the past.
Here are 10 players who Mourinho has sold previously but have since gone on to shine...
Everton striker Lukaku, sold when he was aged 21 by Chelsea in 2014, scored 25 Premier League goals for the Toffees last season - and now appears to be on the brink of a big-money move to Mourinho's Manchester United.
The Belgium international played just twice under Mourinho's Chelsea stewardship but scored 15 times in the top flight while on loan at Everton in the 2013-14 campaign.
Mourinho was not impressed enough to prevent a £30m permanent move to Goodison Park the following summer, though.
Kevin De Bruyne
Manchester City needed to part with £54.5m to bring De Bruyne back to the Premier League, just one season after his permanent move to Wolfsburg from Chelsea under Mourinho.
Mourinho labelled De Bruyne "an upset kid" and criticised his efforts in training, despite playing the midfielder in the first three Premier League games of Chelsea's 2013-14 season in August before selling the midfielder for £18m to Wolfsburg in the same month.
De Bruyne registered 18 assists in the 2016-17 campaign for Pep Guardiola's side, more than any other player in the top flight.
Juventus centre-back Bonucci was deemed surplus to requirements by Mourinho at Inter Milan before going on to win six Serie A titles with Juve. Mourinho allowed the then 22-year-old to leave the San Siro in 2009 for a meagre £3.4m.
Bonucci, 30, was coveted by Guardiola last summer with Manchester City ready to pay £43m for the defender before Bonucci penned a new four-year deal at Juventus in December 2016.
Extending the list of Mourinho rejects nearing a move to the blue half of Manchester is Ryan Bertrand, who could be a Guardiola player before the end of June, according to Sky sources.
Bertrand, 27, spent much of his early 20s on loan away from Stamford Bridge, but despite starting in Chelsea's Champions League final win over Bayern Munich in 2012, Mourinho allowed the England left-back to leave permanently in 2014.
Chelsea's Player of the Year in 2012-13, Mata was soon usurped by Oscar after Mourinho's return to the club at the end of the season, allowing the playmaker to join rivals Manchester United in the following January transfer window.
With six goals and three assists in 25 Premier League appearances for United in the 2016-17 campaign, Mata has become a leading figure for Mourinho at Old Trafford - with the Portuguese insisting the player is more suited to his United side than the Chelsea team he oversaw.
Mourinho allowed David Luiz to join Paris Saint-Germain in 2014 for a £50m fee just a month before a horror show in Brazil's 7-1 defeat to Germany in the World Cup semi-final, justifying the then Chelsea manager's decision.
Luiz has flourished since returning to the club under different management, though, and is now dubbed an Antonio Conte masterstroke following Chelsea's Premier League title win in May.
Mohamed Salah completed a £34m move to Liverpool this summer but the 24-year-old was previously loaned out to Serie A during Mourinho's second spell at Chelsea.
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He enjoyed impressive campaigns at both Fiorentina and Roma before securing a permanent move to the latter where he provided 11 assists in the Italian top flight in the 2016-17 campaign.
The Southampton player was just 23 when he was allowed to leave Stamford Bridge for less than £6m under Mourinho in 2015, but has become a dominant midfield force at St Mary's.
Andre Villas-Boas said Romeu had a "brilliant future" when he was unveiled at Stamford Bridge alongside Lukaku in 2011 after leaving Barcelona, and former Saints boss Claude Puel has claimed the 25-year-old is "not far off" the level of PFA Player of the Year N'Golo Kante.
Allowed to leave Real Madrid under Mourinho at the age of 24, the Argentina international impressed at Benfica and earned a big-money move back to La Liga with Valencia in 2016.
The centre-back is a key player at the Mestalla and has been touted as a possible Chelsea transfer target this summer, according to reports in Italy.
Filipe Luis was signed by Mourinho after stalwart displays in Atletico Madrid's La Liga-winning campaign in 2013-14, but spent just one season at Stamford Bridge before returning to his old side having made just 15 appearances for the Blues.
The Brazilian picked up where he left off at the Vicente Calderon, though, making 48 appearances for the Spanish side in the 2016-17 season as Atleti reached the semi-finals of the Champions League and once again boasted the best defensive record in the Spanish top flight ahead of Barcelona and Real Madrid.