The Blues completed their third and final signing on transfer deadline day, with the 26-year-old midfielder arriving at Stamford Bridge on a temporary deal.
Thomas Tuchel has now added three players to his squad, in the form of Marcus Bettinelli, Romelu Lukaku and Saul.
Bettinelli has signed on a free transfer and will be used as a back-up goalkeeper option behind Kepa Arrizabalaga and Edouard Mendy in between the posts.
Lukaku, meanwhile, has become the club’s record signing, after Chelsea splashed out a whopping £97.5million for the Belgium striker to return to west London.
Now, Saul has completed a loan move to Stamford Bridge after falling down the pecking order at Atletico Madrid recently, and Chelsea supporters will be hopeful that Tuchel can get the Spain international back to his brilliant best.
With all this being said, football.london has taken a look at what Tuchel’s best XI will be when everyone is fit and available to the German coach.
Edouard Mendy (GK)
There’s no question about this one. Despite Kepa’s recent heroics in the Super Cup, Mendy remains Tuchel’s first-choice goalkeeper.
Antonio Rudiger (LCB)
This man has looked like a different player ever since Tuchel arrived in west London earlier this year.
Rudiger has looked imperious at the start of the season, beginning this term how he ended the last.
Thiago Silva (CB)
Now, this was a tough one – and it feels incredibly harsh on Andreas Christensen, who has been amazing recently.
However, Silva was brilliant for Chelsea last season and when he’s fit and available – in the biggest games – he should come into Tuchel’s strongest line-up.
Cesar Azpilicueta (RCB)
The Spaniard looks back to his brilliant best at Chelsea and he should be one of the first names on Tuchel’s team sheet.
Reece James (RWB)
James has been a revelation for Chelsea over the past couple of seasons and looks a shoe-in at the right wing-back spot.
However, the Blues star is now suspended after being sent off in Saturday evening’s 1-1 draw against Liverpool.
Saul Niguez (CM)
Saul has come in on a season-long loan and it would be a massive surprise if Tuchel has brought him in on a temporary deal for the midfielder to sit on the bench.
Jorginho has been brilliant, but unless Tuchel changes his system and runs three in the centre of midfield, the Italy international could sit out.
There’s simply no doubt about this. Kante gets into Tuchel’s first team and any suggestions otherwise would be massively frowned upon by the whole of the Chelsea fan base.
The France international is one of the best central midfielders in world football and will be integral for the Blues if they are to mount a serious title challenge this season.
Ben Chilwell (LWB)
Despite Marcos Alonso ‘s fantastic start to the season, Chilwell is surely Tuchel’s first choice for the left wing-back role going forward.
The former Leicester City defender has adapted seamlessly to life at the Blues since making the big-money move last summer.
Mason Mount (CAM)
Mount has been simply outstanding for Chelsea over the last two seasons and has cemented a place in Tuchel’s side.
There is plenty of competition, with the likes of Christian Pulisic, Timo Werner and Hakim Ziyech all unfortunately missing out, but Mount had to be in here.
Kai Havertz (CAM)
Saturday evening’s draw with Liverpool showcased just why Havertz is so crucial to this Chelsea set-up, as he scored a fantastic looping header over Alisson at Anfield.
The Germany international looks to be growing into his role more and more as his time at the Blues rolls on. Havertz has proven in his short stint at a Chelsea player that he is a man for the big occasions as well.
Romelu Lukaku (ST)
The big signing of the summer from a Chelsea point of view. £97.5million from Inter Milan, this man is not here to sit on the bench.
Lukaku has started both of the Blues’ last two games and he has looked in fine form. The Belgium international opened his Chelsea account – for a second time – in their win against Arsenal recently, and caused Liverpool numerous problems at Anfield at the weekend.