The 32-year-old left Stamford Bridge at the end of his contract after a seven years at the club, with Chelsea only willing to offer him a two-year deal rather than the player’s desired three years.
Arsenal moved into pole position to sign the Brazil international by offering a three-year contract last week, and are on the verge of beating off competition from Barcelona and Inter Miami.
Along with the length of the deal, joining Mikel Arteta’s rejuvenated side and the chance to work with fellow Brazilian Edu are the reasons Arsenal are favourites to secure Willian’s signature.
Willian made 47 appearances for Chelsea in all competitions and finished the season in fine form, with four Premier League goals after the restart taking his tally for the season to nine.
Local foes very rarely choose to do business with each other but in recent years Arsenal and Chelsea have flouted the unwritten rivalry rules, with several players having surprisingly moved between the two sides.
With Arsenal understood to have offered Willian a three-year contract offer, we assess the impact of those who crossed between north and west London.