Benfica coach Jorge Jesus has urged his team to learn from their mistakes when they visit Barcelona on Wednesday.
The Liga Sagres giants are second in Group G heading into the Champions League clash but must match Celtic’s result to advance.
It means Benfica are likely to have to beat Barcelona at the Camp Nou, with Celtic favourites to dispose of Spartak Moscow in Glasgow.
Jesus, whose team suffered a 2-0 loss to the La Liga giants last time they met, said they needed to rectify where they went wrong in Lisbon on October 2.
“What do we have to do different now? We must look to the other match against Barcelona and improve some of the areas where we struggled against them,” he said.
“We did some good stuff in the first leg and we know that so we should do it again tomorrow.
“We must improve our good points and try and correct our mistakes, and also try to put some pressure on Barcelona.
“They have very efficient positioning and individual skills. We didn’t manage to play in the last third of the pitch. They are the best team in the world at passing the ball so we barely saw it in their half.”
Barcelona are assured top spot in the group and are likely to rest several first-team players for the clash.
Jesus said a weakened Barca side was none of his concern and pointed out the injuries he must cope with.
“It is true, but it is true as well that Benfica won’t have four important players at its disposal – (Pablo) Aimar, Carlos Martins, Enzo (Perez) and Salvio,” he said.
“You don’t discuss that when two big clubs are facing each other because us and them have a number of good players in our squads.
“Barcelona is a very strong team and so is Benfica. We have to give an answer (to criticism of performance against Celtic) during the match with the players we have.”