Ahead of the London derby, we look at five players who have played for both teams.
The current Chelsea manager joined the West Ham academy in 1994 and went on to play for the Irons until 2001, where he made 172 appearances. Lampard then made the switch from east to west London to join the Blues for around £11m.
It was at Chelsea where he made a name for himself, becoming the club’s all-time top goal scorer with 211 goals to his name, as well as winning three Premier League’s, the Champions League, four FA Cups, two League Cups and the Europa League.
Now that he’s the Chelsea boss, let’s hope he can replicate the success he enjoyed as a player!
Like Lampard, Joe Cole started his football career at the Hammers, joining as a youngster in 1990. He then moved to Chelsea in 2003 and became one of Roman Abramovich’s first signings since taking over the club.
In a blue shirt, Cole won three Premier Leagues, three FA Cups and two League Cups before joining Liverpool in July 2010 as a free agent. Whilst in Merseyside, he made a return to West Ham on loan in the 2013/14 season.
Moses spent the 2015/16 season on loan at West Ham, where he only twice for the Irons. He then returned to Chelsea and was one of the stars of their title winning campaign under Antonio Conte in the 2016/17 season.
He is now on loan at Inter Milan and reunited with the Italian manager.
Born in Sèvres in France, Ba spent his youth career at Port Autonome, Frileuse and Montrouge before signing for Rouen in 2005.
After spells at Mouscron and Hoffenheim, he made the move to England and joined West Ham in January 2011. Despite scoring 7 goals in his short spell at the club, it wasn’t enough to help save the Hammers from relegation. He then made the move up north to Newcastle.
He was very impressive on Tyneside, so much so that Chelsea signed him up in January 2013, with the Senegal international scoring a brace on his debut away at Southampton. Ba now plays for Istanbul Basaksehir.
Despite never making an appearance for West Ham, Terry spent the first four years of his youth career at the east London club. He then moved to Chelsea at the age of 14.
Terry went on to play for the club 717 times, scoring 67 goals in total. He also has five Premier Leagues, five FA Cups, three League Cups, a Champions League and a Europa League to his name.