He was not involved in Arsenal’s Community Shield victory but has now teamed up with his teammates for his first session at London Colney.
Mesut Ozil was also back with Arteta’s squad, although new signing Gabriel Magalhaes has yet to start training after recently completing his move from Lille.
Here are five things we noticed during Arsenal’s last session.
(Image: Arsenal FC via Getty Images)
Eager to impress
Willian looked relaxed during his first session as he smiled alongside his teammates on the field path.
But once he got into action, he looked fully focused and eager to impress.
Arteta is expected to deploy the Brazilian in a central role which has mostly been used on the right during the later stages of his Chelsea career.
Arriving in the Emirates gives him an exciting new challenge and it is clear that he already wants to impress.

(Image: Arsenal FC via Getty Images)
Way back to Ozil?
Mesut Ozil’s days at Arsenal seem numbered without having played a game for several months.
But he has made it clear he has no intention of leaving the club until his contract expires next summer.
With that in mind, could he find a way to get back into the fold?
Arsenal’s midfielder options are limited and Arteta says he’s made it clear to Ozil what he needs to do to challenge himself.
He was in training with the first team again on Thursday and Friday and the best logical solution is for him to overturn and look to offer something to Arteta’s plans.

(Image: Arsenal FC via Getty Images)
Saliba steps up things
Big things are expected of William Saliba this season – but he faces a period of adjustment.
Mikel Arteta recently admitted that it will take a while for the young defender to level up.
With this in mind, these first sessions will be crucial.
He was pictured in training picking up the ball and looking to work on the pace of English football as he aims to make an instant impression in the Premier League.

(Image: Arsenal FC via Getty Images)
Salah straight into it
Arsenal recently confirmed the signing of their own Salah – capturing the young prospect from Feyenoord.
Salah-Eddine, 17, signed a free transfer to join the professional development phase.

(Image: Arsenal FC via Getty Images)
But he’s already been included in some first-team sessions as one of the many young prospects involved.
The creative midfielder hopes to carve out a bright future for himself in the Emirates and will look to take his first chance to make a lasting impression on Unai Emery.
Young receives the call
Several young players had the opportunity to impress Mikel Arteta.

(Image: Arsenal FC via Getty Images)

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The latest is Tolaji Bola, who took part in first team training on Thursday and Friday this week.
Bola, 22, is yet to make his first-team debut but the left-back is highly rated at the club.
He hopes to make his mark and work his way into Arteta’s squad rotation ahead of a season with a grueling schedule.