When he opted to join Chinese Super League team Shanghai SIPG in 2017, his career quickly slipped into obscurity. With a £60 million bid for the Brazilian midfielder, the Chinese club surpassed the Asian transfer record.

Oscar, who was only 28 at the time and at the prime of his career, got bids from Atletico Madrid and Italian clubs.

#5 Alex Song

Despite joining Arsenal in 2005, it wasn't until 2008 that Alex Song's career took off. Since then, he has played an important role in Arsene Wenger's plans and has become an important member of the team.

Song was in charge of performing the hard labour in the centre of the park, allowing Fabregas and Nasri to concentrate on their creative roles.

Song, however, abandoned a good career when Barcelona offered to treble his pay in 2012. Despite knowing that he wouldn't get much playing time in the absence of Xavi, Iniesta, Busquets, Fabregas, and Keita, Song opted to make the transfer.

He only appeared in 39 games for Barcelona and was soon the subject of serial moves. Alex Song faded from view during periods at West Ham and Rubin Kazan, and his career never recovered.

He is presently 34 years old and plays for Arta Solar 7 in Djibouti.