Former Barcelona midfielder Deco has backed the Spanish giants to progress to the Champions League semi-finals at the expense of Paris Saint-Germain.
However, the former Portugal international believes that PSG will "make things difficult" for the Blaugrana.
"I've seen some [of their] games and I think PSG, despite being a team in formation, will make things difficult for Barca," he told ESPN Brasil. "[Coach Carlo Ancelotti] has experience in the Champions League.
"[Barcelona] have long played together, while PSG are a team that are still under construction. Of course, one cannot underestimate the French because they have quality players like [Zlatan] Ibrahimovic and Thiago [Silva], a very strong defence and a quality midfield."
Deco won the Champions League with Barcelona in 2006.