Arsenal head to the Stadium of Light without their first-choice centre-back, and without an answer to when they will get him back.

William Saliba has not played since aggravating a back problem at the 2026 World Cup semifinal against Spain, and Mikel Arteta this week refused to put a timeline on his recovery.

“We don’t really know the amount of weeks he is going to be out because it’s about a healing process, in every human being it’s a bit different,” Arteta told reporters.

The manager described the trend as encouraging without promising a date.

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“The progression has been really positive in the last few weeks but we need to wait and see how that back problem react when we start to put some load into it.”

Arsenal have been briefed on the practical floor: Saliba is not expected back until at least October, and a longer absence remains on the table.

An ‘easy decision’ to keep Saliba in Europe

Saliba’s name still sits on Arsenal’s Champions League roster for the league phase running from September to January, a call Arteta described as an “easy decision” despite the open-ended layoff.

That commitment matters. Arsenal opened their European campaign on Tuesday with a 1-0 win at Napoli, Martin Ødegaard’s strike 15 minutes from time separating the sides at the Stadio Diego Armando Maradona. Eight league-phase games will demand a settled centre-back pairing, and Arteta is banking on getting Saliba back before the league phase ends.

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‘We have lost an incredible player’

Timber’s own return is finally coming into view. The Dutch defender has been out since summer groin surgery, and Arteta confirmed on Friday that he had rejoined first-team training.

“He has been training with us now for a few days, and he looks in good shape.”

That is a lighter tone than the one Arteta struck when both defenders were first ruled out in August.

“We have lost an incredible player. Same with Jurrien,” he said at the time.

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Mosquera edges closer to a return

Without Saliba, Arsenal have leaned on Gabriel Magalhães, Piero Hincapié and Riccardo Calafiori across centre-back, with Ben White holding down right-back after Arteta insisted “he’s fine” following a midweek scare in Naples.

Cristhian Mosquera, the summer signing who has been managing a muscle problem, is edging into contention.

“He is doing really well. Let’s see if he can get this game or the next one,” Arteta said.

Kick-off against Sunderland is at 8pm local time on Saturday at the Stadium of Light. The hosts are without Romaine Mundle (knee) and Habib Diarra (thigh), while deadline-day signing Malick Fofana is expected to make his full Premier League debut.

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