Carragher believes Arsenal made a major transfer mistake by failing to sign Barcola this summer. The France international recently completed a stunning £123 million move to Liverpool, signing a five-year contract at Anfield.
Arsenal explored a deal for the 24-year-old earlier in the window but eventually shifted their focus elsewhere. This decision ultimately gave Andoni Iraola's side a relatively free run to secure the double Champions League winner.
Arteta has spent the last two summers searching for an elite left winger to bolster his squad. However, the Gunners have continually missed out on their primary attacking targets in that position.