According to the father of Thomas Vermaelen, the Arsenal and Belgium central defender will be out for approximately six weeks after suffering an Achilles injury in Arsenal's UEFA Champions League playoff tie against Udinese. Vermaelen reportedly had surgery on his Achilles over the weekend, but Arsenal have not confirmed themselves how long they expect Vermaelen to be unavailable for selection.
Arsenal have, at least on paper, some decent depth in the center of defense. Whether or not there is a significant quality drop-off after Vermaelen is up for debate, but the Gunners at least have some bodies. New signing Per Mertesacker is expected to partner Thomas Koscielny in the center of defense in Vermaelen's absence. The Gunners also have Sebastian Squillaci, who has been reasonably reliable but failed to impress since arriving, as well as Johan Djourou, a man with an injury history the size of the New York yellow pages.
For more on Arsenal FC and how they'll get on without Vermaelen, check out The Short Fuse.