Barcelona go into their second leg at Camp Nou locked at 0-0 with Milan as they bid to become the first side to retain the trophy since it evolved from the European Cup into its present form for the 1992-93 season. Chelsea have a 1-0 lead over their Portuguese opponents, who will be seeking to improve on a disappointing display in the first leg.
The other two quarter-finals should see nine-time winners Real Madrid and four-time champions Bayern Munich progress, as they host APOEL and Marseille having won 3-0 and 2-0 away respectively last week.
Lionel Messi. Photo: AFP
Barcelona will be looking to dominate Milan in the same manner they did at San Siro, where they were left frustrated both by the pitch and some outstanding defending by the Italian side.
The Catalan giants will be boosted by the return of Cesc Fabregas, who sat out the first leg and the league win over Athletic Bilbao on Saturday because of a lower back injury.
"We've dealt with it and today (Saturday) he was better," said Barca coach Pep Guardiola. "So even though we were forced to leave him out against Bilbao, he will be there on Tuesday."
Barcelona attacker Pedro Rodriguez said that he and his team-mates needed to be especially vigilant against a Milan side that forced a 2-2 draw in injury time of their group-stage game at Camp Nou earlier this season.
"Milan have some great players and there is no doubt that they will make life difficult for us," he said.
"Even if we dominate the game, we cannot afford to be complacent because they are capable of scoring at any moment.
"They are a tough team to beat but, with the crowd behind us, we are hoping to put in a good performance and get through to the next round."
The author of a fine solo goal for Milan in the 2-2 draw, Alexandre Pato could be thrown into action after returning from the United States, where specialists examined the muscle problems that have kept him out since February 25.
"He is ready and available for selection by (coach Massimiliano) Allegri," said club doctor Jean-Pierre Meerssman.
Allegri rested 36-year-old veteran defender Alessandro Nesta for the weekend 1-1 draw with Catania, while 35-year-old Dutch great Clarence Seedorf also took it easy as they bid to repeat their outstanding performance from last week.
Allegri, though, has doubts over another Dutch veteran, Mark van Bommel, who was suspended for the first leg but is struggling to recover from a back problem.
Fernando Torres. Photo: AFP
Chelsea have been like a club reborn since Roberto Di Matteo replaced Andre Villas-Boas, winning six of their eight games under the Italian's stewardship, and enter the Benfica clash with their confidence sky-high.
However, Di Matteo has fitness concerns over Didier Drogba and David Luiz ahead of the match.
"David has a problem with his ankle at the moment. We will have to assess how he is and I don't know about Wednesday," Di Matteo said.
"Didier is another one we will have to assess over the next 48 hours."
Benfica must contend with the daunting statistic that only two clubs have lost a home game in the Champions League knockout stages and gone on to win -- Ajax against Panathinaikos in the semi-finals of the 1995-96 edition and Inter Milan last season against Bayern Munich in the last 16.
Benfica coach Jorge Jesus, though, is adamant that his side -- who progressed at the expense of English champions Manchester United at the group stage -- can pull off a shock.
"We didn't deserve to lose the first leg; they took their one and only chance," he said. "However, we can go there and get a result because we've scored in all our away games so far so we can easily go there and win."