IN the 2020 summer window, Willian became the latest star to officially play for both Arsenal and Chelsea.
The Brazilian, 31, swapped the blue for red as he joined an ever-growing list of player to move across London.
From Petr Cech and Ashley Cole to Nicolas Anelka and Olivier Giroud, those players could form a handy team of their own.
Check our combined best XI of players to have starred in both the red of Arsenal and blue of Chelsea… with Willian just about making the cut.
CECH spent over a decade at Chelsea between 2004 and 2015, winning four Premier League titles, the Champions League in 2011-12 as well as nine other trophies.
But Cech, now 39, moved north to the Emirates – where he spent the final four years of his career – winning the FA Cup and two Community Shields.
He's now back at Chelsea as technical director – and last season even made the 25-man Premier League playing squad to provide back up to Edouard Mendy and Kepa Arrizabalaga.
DIARRA joined Chelsea from Le Havre in 2005 – where he made just 13 Premier League appearances.
Diarra, 37, joined Arsenal two years later, where he last just one season, playing seven times before moving to Portsmouth… and then, bizarrely, Real Madrid.
He then played for several Russian sides and Marseille before ending his career at Paris Saint-Germain in 2019.
BEFORE Willian, Luiz was the most-recent mover when the Brazilian was a surprise deadline day arrival for Arsenal in an £8m deal last summer.
The Brazilian, 34, spent six years at Stamford Bridge across two spells at the club – but left after being told he would not be an automatic starter.
He left Arsenal last summer after his contract expired and now plays back home for Flamengo.
ANOTHER to move straight from Chelsea to Arsenal, Gallas earned cult hero status at the Blues between 2001 and 2006 – having first joined before Roman Abramovich's cash injection.
The Frenchman, 44, played 159 league games for the Blues and featured over 100 times for the Gunners too.
But his London tour didn't stop there, with Gallas then spending three years at Tottenham before retiring in 2014.
ARGUABLY the most controversial Arsenal to Chelsea mover, Cole spent a decade at Highbury having worked his way through their youth ranks.
After 159 games at Arsenal, Cole, 41, went on to have success at Chelsea, playing 229 Premier League matches – winning one title, to go with his two from the Gunners.
Cole is looked at fondly by Blues supporters, but less so by Arsenal who never got over his betrayal.
Cole is now a first-team coach under Frank Lampard at Everton.
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