Arsenal vs Chelsea live: Arteta updates Timber, Saliba and Guimaraes ahead of Sunday clash

Sunday's biggest Premier League fixture just tightened

Mikel Arteta has confirmed William Saliba remains unavailable and said decisions on Jurrien Timber and Bruno Guimaraes will wait until Saturday training. That is the kind of squad news that shapes the first London derby of the Premier League season.

Arteta told reporters Guimaraes picked up a knock against Aston Villa and was being assessed, while adding he was hopeful the midfielder would train on Saturday. Timber is back training with the group, but the manager said the club would decide after that session whether he is ready for Chelsea. Gabriel Mosquera's earlier substitution was described as precautionary.

The update lands with Saturday's board already full and Sunday reserved for the first heavyweight Premier League meeting of the campaign. Arsenal sit on a perfect start. Chelsea arrive with the same record. Viewers will be watching not only the scoreline but which centre-backs and midfielders Arteta trusts after a compressed week.

What the squad picture actually is

Saliba's continued absence is the hard fact. Arsenal have already submitted their 25-man Premier League squad following the close of the summer window, alongside a large Under-21 group, so the registered options are now fixed until January. That makes every fitness call around Timber and Guimaraes more than a routine team-sheet note.

Chelsea have been quieter on midfield availability. Separate reporting around the same press cycle noted no fresh public update on Moises Caicedo. Neither club has issued a final matchday squad at the time of writing.

Where to watch will depend on territory; check the official Premier League and local rights-holder schedules. In several markets the Sunday 16:30 BST kick-off is treated as the weekend's flagship fixture.

Saliba is out. Timber and Guimaraes are in the assessment window. That is the picture before Sunday.