Uncertainty surrounds Bacary Sagna, but Arsenal should not countenance allowing him to leave in the January window -- the Frenchman remains absolutely vital to the Gunners' title bid.
Since arriving at the club from Auxerre in July 2007, Bacary Sagna has become one of Arsenal's most reliable performers. For more than six years, he has been a constant and consistent figure in the full-back position. His fellow professionals have twice voted him into the PFA's Team of the Year, and in April 2012 Arsene Wenger proudly declared that he considered Sagna to be the best right-back in the Premier League.
However, Sagna's future is currently very much up in the air. His existing contract expires at the end of this season, and as yet no extension has been agreed. Wenger has stated his optimism about the prospect of concluding a new deal, but recent comments from the Frenchman will have caused alarm among the Arsenal fans.
"I've still got six months on my contract with Arsenal," Sagna told beIN Sport. "We are in negotiations. It's an option to go somewhere in January but I always had a good relationship with Arsenal."
Sagna may consider it an option to go somewhere in January. For Arsenal, however, it would be a disaster. He has been an integral part of Arsenal's improved back four. Last season, he struggled for both fitness and form. It's understandable, really -- Sagna suffered the remarkable ill fortune of two broken legs inside two years.
However, he now appears to be back to his best. Alongside Laurent Koscielny, Per Mertesacker and Kieran Gibbs, he has helped put an end to the defensive chaos that dogged Wenger's team for so many years. Despite shipping six goals against Manchester City last week, the Gunners still boast one of the meanest defences around: in the Premier League, only Southampton and Everton have conceded fewer goals.
Replacing Sagna with a like-for-like signing in January would be next to impossible. What's more, many of Europe's best full-backs would be cup-tied for the looming Champions League tie with Bayern Munich, in which Arsenal will come up against one of Europe's best left-wingers, Franck Ribery.
If Sagna were to go, Wenger might be forced to promote Carl Jenkinson to the first team. The prospect of Ribery running at Jenkinson is one that would send shivers down the spine of even the most bullishly confident Arsenal fan.
There's no doubt that Jenkinson has potential. At just 21, he already has a senior England cap to his name. His desire and commitment are unquestionable, and he is arguably the finest crosser of a ball in the Arsenal squad. However, he cannot compare to Sagna in several key areas.
His relative inexperience means his positioning is often not up to scratch, and he also struggles to impose himself in the air. Although Jenkinson is the taller player, Sagna has superior spring and heading ability. It makes him invaluable when it comes to defending set pieces, which is a historical weak point for Arsenal.
However, it is not just at right-back that Sagna is needed. His aerial prowess and positional intelligence mean that he can also be deployed at centre-back. He impressed in that unfamiliar role in the win over Sunderland in September, and may yet be required to fill the breach again between now and the end of the season.
The recent injury to Koscielny at Manchester City was a stark reminder of Arsenal's lack of depth at centre-half -- as it stands, Thomas Vermaelen and Per Mertesacker are Arsenal's only fit senior centre-backs. If one of them were to pick up a knock, Sagna would be next in line.
His versatility, as much as his excellence, makes him a player that Wenger cannot contemplate losing. If a new deal cannot be agreed, it would be better to let him leave on a free transfer at the end of the season than to allow him to depart in January.
If the Gunners want to maintain their title charge, keeping Sagna will be crucial.