Having already lost away to Celtic and AC Milan in this season’s campaign, Wenger believes the Catalan club have lost their air of invincibility, though PSG must nevertheless find a way to stop Lionel Messi.
"Seeing as Celtic and AC Milan have managed to beat Barcelona, anything is possible for a team like Paris Saint-Germain," wrote Wenger on his Eurosport blog.
"Barcelona are not invincible. It's clear that Barca are the superior side technically, but they have lost a bit of spark recently."
Citing defensive frailties and the French club’s attacking firepower, spearheaded by Ligue 1 topscorer Zlatan Ibrahimovic, the Premier League manager has suggested a weakness in Tito Vilanova’s side.
"They [Barcelona] are now more vulnerable at the back and I believe that PSG have enough attacking potential to exploit this vulnerability which did not exist in previous seasons," Wenger continued.
Despite backing an upset, the Gunners boss is adamant that success will be impossible for PSG if they cannot find a way to stop Messi, who has bagged an astonishing 43 La Liga goals this year.
|14/1||Lionel Messi is 14/1 with BetVictor to score a hat-trick against PSG|
"The Argentine is vital to Barça's attack and he scores between 60 and 70 per cent of their goals. But the other challenge for PSG is to make sure the other players don't compensate for Messi."
Even though PSG’s ranks are well stocked with high-profile names, such as Ibrahimovic and Thiago Silva, Wenger singled out 25-year-old Blaise Matuidi as the French side’s key player against the Liga leaders.
"Matuidi will have a huge bearing on what happens in these games," added the Arsenal boss. "He could even compensate for what happened between France and Spain last week.