Arsenal legend Alan Smith believes Unai Emery's side have done well this season but are still awaiting a stern test.
The Gunners have won nine on the bounce after losing their opening two matches to Manchester City and Chelsea.
"With this as a possibility, you can't blame the fans for getting excited, singing "We've got our Arsenal back!!" at Craven Cottage," Smith wrote in his column for the Evening Standard.
"That's not true though. Not yet at least. 'Their Arsenal' will be the free-flowing outfit capable of scoring against anyone but also savvy and ruthless, capable of grinding out clean sheets. Conceding eight goals in nine games is far from ruthless.
"Still, I can see the winning run continue against Claude Puel's lot. The acid test comes at the start of November. It might be time to get excited if Arsenal beat Liverpool."