The Brazil international has allegedly agreed a three-year contract with the Gunners as he prepares to leave Stamford Bridge later this month following the expiration of his contract.
The 31-year-old has enjoyed another productive campaign for the Blues, scoring 11 times and providing nine assists in 47 appearances in all competitions.
Here, Sports Mole looks at the shirt numbers available for Willian at the Emirates Stadium should he arrive ahead of the new season.
Willian had the number 22 shirt at Chelsea between the start of the 2013-14 campaign and the end of last season before taking on '10' following Eden Hazard's switch to Real Madrid.
Aside from a short spell with the number 88 at Russian side Anzhi Makhachkala, Willian has only ever sported '22' or '10' during his club career, but he has also had the number 19 and number seven for Brazil.
The number 10 at Arsenal is currently occupied by Mesut Ozil, and it would not be a surprise to see the experienced attacker leave the Emirates Stadium this summer despite recent comments from his agent.
As a result, '10' could be available at the Gunners next term, but Pablo Mari currently holds the number 22, with the central defender recently joining the club on a permanent deal.
The number 11 could also be available depending on Lucas Torreira's future, with the Uruguay international potentially on his way out of the club during this summer's transfer window.
The number 12 and number 13 are also both currently available, while '15' could open up if Ainsley Maitland-Niles were to depart the club ahead of the 2020-21 campaign.
Carl Jenkinson's previous '25' has also not been filled since the end of last season. However, Willian would surely want one of the so-called glamorous numbers if he were to arrive this summer and '10' is perhaps the one to keep the closest eye on as Ozil's future continues to be called into question.