Wingers - Mohamed Salah (Liverpool) and Andre Schurrle (Fulham)
Chelsea signed Mohamed Salah in January 2014 when the Egyptian was close to signing for Liverpool. He played 19 games for them and scored 2 goals before he was sent on loan Fiorentina.
Salah hit the ground in the Serie A and he eventually joined Roma on a permanent deal. He scored 34 goals in 83 games for the Italian giants before signing for Liverpool in 2017.
The 26-year-old had an unbelievably good season for the Reds and broke the Premier League record for most goals in a single season by scoring 32 goals in 36 league games. In all competitions, he scored 44 goals in 52 games.
Andre Schurrle joined Chelsea for £18m in the summer of 2013. He was at the club for a season and a half scoring 14 goals in 65 games before returning to the Bundesliga with Wolfsburg.
The World Cup winner moved to Borussia Dortmund in 2016 before returning to the Premier League with another London club in Fulham this summer.
Schurrle won the Premier League with Chelsea in 2014/15 although he was at the club for only half the season.
Honourable mentions - Juan Cuadrado (Juventus), Bertrand Traore (Olympique Lyon), Thorgan Hazard (Borussia Monchengladbach) and Christian Atsu (Newcastle United)