Former Arsenal defender Kenny Sansom feels the absence of Carles Puyol and Gerard Pique could be the key to Barcelona's undoing against the Gunners.
The two centre-halves, who usually play key roles in the Spanish giants' regular set-up, will be absent for Tuesday night's UEFA Champions League last-16 clash at Camp Nou due to injury and suspension respectively.
And Sansom, who played at left-back for the Gunners for eight seasons in the 1980s, feels that duo's absence will give Arsenal a 'massive boost' as they bid to build on their 2-1 aggregate lead.
"Obviously the two centre-halves, Pique and Puyol, aren't playing so that's going to be a massive, massive boost to Arsenal," he told Sky Sports News Radio.
"To have their two centre-halves (out), who are fantastic players, and who I think are good leaders as well, that could cause them problems.
"I think it does make them weaker. They're a team that really like to perform in their opponents' half.
"It's just a shame that Theo Walcott isn't fit because I think there will be a bit of space in behind Barcelona.
"I think that's where Arsenal can maybe take the game to Barcelona a little bit. If they can get crosses into the box, maybe they can cause some problems."
Arsenal are expected to adopt a more defensive-minded approach than usual at Camp Nou as they look to preserve their advantage, but Sansom is doubtful over their chances of keeping Barca out with the likes of Lionel Messi in the hosts' weaponry.
"I think Barcelona will definitely score, I really do," said the former England star.
"When you've got someone like Messi, he goes past people for fun, he creates things, he's a great finisher, he scores goals with his head.
"They can all score goals, they're a fantastic team and they play at such pace.
"It's a difficult one for Arsenal. It's very difficult to go for 0-0 or to try and get a draw or a clean sheet, which obviously would see Arsenal through.
"They're just such an incredible side and Arsenal are going to have to be at their best."
What will be the outcome in the match Barcelona vs Arsenal?