Mikel Arteta is approaching a decision that most managers would welcome: how to fit a fully fit William Saliba back into a defence that has functioned superbly without him.

The France international has returned to full training at Arsenal's base after missing the entire season so far. Saliba withdrew from France's World Cup semi-final defeat to Spain with a back problem and, following consultations with a specialist, opted for a lengthy rehabilitation programme rather than surgery. No firm return date was ever announced by the club.

Konsa's seamless arrival

In Saliba's absence, summer signing Ezri Konsa has made the transition from Aston Villa look effortless. The England international cost Arsenal £55 million and joined just hours before the club's opening match against Coventry, making his debut as a substitute against his former club Aston Villa.

Konsa has since started seven of Arsenal's nine Premier League fixtures alongside Gabriel Magalhaes, and the partnership has helped the Gunners concede just five league goals — the fewest in the division. Arsenal sit top of the Premier League, and some observers have described Konsa and Gabriel as the finest central defensive pair in world football.

The 29-year-old had spent years establishing himself at Aston Villa — making 286 appearances after joining from Brentford in July 2019 — and was part of the Villa side that lifted the UEFA Europa League in May. He has also cemented his place in the England setup, starting seven of the eight matches the Three Lions played at the World Cup, including a quarter-final appearance at right-back against Norway.

His commanding displays have not gone unnoticed. Konsa scored the opener in Arsenal's 2-0 victory over Everton and delivered another assured performance as the Gunners beat Liverpool at Anfield for the first time in 14 years.

Arteta's selection puzzle

Saliba, 25, had been managing his back complaint throughout last season, when he and Gabriel formed the defensive backbone of the side that claimed Arsenal's first Premier League title in 22 years — conceding only 27 league goals. Saliba was named in the PFA Team of the Year for the fourth year running.

Arsenal are set to host Hull before the next international break, giving Saliba additional time to build his fitness. Once he is available, Arteta must find space in a backline that already includes Konsa, Gabriel, Ben White, and Jurrien Timber.

One option is to shift Konsa — who made his England debut at right-back — out of the centre, allowing Saliba to reclaim his traditional position alongside Gabriel. Arteta prizes physicality across his defence and a right-back role would suit Konsa's imposing physical profile.

Saliba's return also dims the prospects of young centre-back Cristhian Mosquera, who has had limited minutes this season and is still recovering from a hamstring injury. Questions about his future at the club are likely to intensify.

Arsenal played 63 games across all competitions last season as they won the Premier League and reached the UEFA Champions League final. With Arteta targeting back-to-back titles and European glory this time around, a deep, competitive squad — including a fit-again Saliba — will be essential to sustaining a challenge on multiple fronts.