The German is set to miss several months of the season after suffering a knee injury in the match against Lens.
Arsene Wenger's admittance that he was prepared to dip into the market to bring in defensive cover after news of Per Mertesacker's injury, as covered on BBC Sport, may not end up giving Gunners fans the player they hope for.
Mertesacker's injury is expected to keep the German out for several months, with Sky reports suggesting it could be as many as five months - something that would see him not available until around Christmas.
Arsenal supporters may hope it leads their manager to make a world class signing in defence, but that may not be the case.
Though Wenger stopped short of disclosing how long the 31-year-old was set to be out, he did admit that he would be out for "months".
Bolton's Rob Holding in action with Eastleigh's Kaid Mohamed
It leaves the club very short at the back, despite the signing of Rob Holding. They currently have just Laurent Koscielny and Gabriel as options there, with a number of other players that can fill in, but even those two may not be ready for the start of the season, with the Frenchman recovering from his European Championship tournament and the Brazilian struggling with tonsillitis.
Because Mertesacker will likely return in under six months, the Gunners are unlikely to make a big name, big money signing - something many fans thought Wenger needed at the back even before the ex Germany international's injury.
Arsenal manager Arsene Wenger
It is not Wenger's methods to be rushed into an expensive transfer that he hadn't prepared for, and it is feasible that Holding was set to be the club's only business in that position before Mertesacker's injury.
With central defence not necessarily a position the Frenchman would have strengthened more, his admittance that he is prepared to bring in someone with experience could point to a more temporary fix, or an older player that might sign on a single-year contract.
Sunderland's Jermain Defoe shoots wide under pressure from Arsenal's Per Mertesacker