The north London side already trail league leaders Chelsea by 12 points after a second-half collapse saw Swansea City beat Arsenal 2-1 at Liberty Stadium.
You never feel Arsenal will make the big signings in the vital positions that they need to take them there
And former Liverpool defender Carragher reckons the Gunners have not progressed over the summer despite showing signs of promise in the league and winning the FA Cup last season.
“If you think of this stage last season, they were top of the league with a bit of a lead [six or seven points],” Carragher told Sky Sports.
“I don’t think anyone really believed that they could go on and win the league.
“The problem for Arsenal is, and any team, you always want to feel like you’re progressing and moving forward.
“That is the frustration. Arsenal seem the same or going slightly backwards.
“Considering last season, they won the FA Cup and they were contending for the league in February.”
Alexis Sanchez, who moved to Arsenal in a £35m deal from Barcelona in the summer, broke the deadlock before Gylfi Sigurdsson and substitute Bafetimbi Gomis turned the game on its head.
And ex-England international Carragher says Wenger failed to address key weaknesses in his side, unlike his contemporary Jose Mourinho, who signed Diego Costa and Cesc Fabregas this summer.
“If you look at Chelsea, they didn’t win anything last year. I don’t know what the points difference was between them and Arsenal. It was close,” added Carragher.
“They make big signings and we think they’ll win the league. You never feel Arsenal will make the big signings in the vital positions that they need to take them there.
“Nothing between Chelsea and Arsenal last year, but now, they seems miles apart. Jose Mourinho identified certain positions and improving it. Now, they look unstoppable.”
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