The Gunners could only muster a fifth-place finish in 2016-17, with Arsene Wenger slipping out of the continental elite for the first time in his iconic reign.
Inconsistency in the current campaign has Arsenal on the outside looking in once again, with the north London outfit currently sat sixth, eight points adrift of the Champions League spots.
They are, however, through to the last-32 of the Europa League and emulating Manchester United’s achievements from last season – when they took the trophy – could provide the Gunners with the clearest path back to European football’s top table.
Pires believes the time has come for Wenger to shift focus, with the former Arsenal star telling The Sun: "The Europa League has to be Arsenal's priority now, already.
"The objective has to be to do what Manchester United did last season – they are a good example.
"United won the Europa League and went straight into the Champions League – for Arsenal it is very important to get this state of mind.
"It’s a trophy, a good trophy, so it’s very important. And this season it is the last opportunity Arsenal have of making the Champions League.
"Unfortunately, but if you see the table it’s very difficult for Arsenal to reach the top four.
Arsenal look to be heading forward in Europe, having established a 3-0 first leg lead in a last-32 meeting with Osterstunds, and Pires believes they can go all the way if the draw remains kind and they can avoid fellow heavyweights.
He added: "Atletico and Arsenal are the favourites, for me this is the final in Lyon.
"They both have a lot of experience, especially in the Champions League.
"They just need to avoid each other and Celtic if they want to face each other in the final.
"I love Celtic. It is not easy for any team, especially in Celtic Park. The atmosphere is amazing.
"When you are a player, inside, playing against Celtic, it is a great atmosphere. It is still very close to the pitch, maybe only Liverpool has a similar atmosphere.
"That’s why it is very difficult to win in Celtic Park."