Barcelona coach Pep Guardiola faces the biggest test of his debut season when the Spanish powerhouse meets French champion Lyon in the return leg of their Champions League final-16 matchup.
Lyon has a challenge of its own with France striker Karim Benzema still in doubt to start for Wednesday's match.
Benzema was replaced at halftime in Lyon's weekend loss to Lille due to a hip nagging injury, which has been bothering him for nearly 10 days.
"I have a few problems but, yes, I think I can play," Benzema said, according to Spanish daily Sport. "I don't want to lose this match for anything in the world."
The two clubs head into the match at the Camp Nou following a 1-1 draw at Lyon in the first leg.
Guardiola's rookie season has been close to perfect, with the Catalan giants picking up a victory over the weekend to snap a winless slide and recoup extra points over Real Madrid atop the Spanish league.
Barcelona is already through to the Copa del Rey final and must overcome Lyon _ and an 0-3 record against French clubs in two-legged series _ to keep its European hopes and the elusive treble bid alive.
"The most important thing is ourselves," midfielder Seydou Keita said. "If we're good, we'll win the game."
Guardiola will be without captain Carles Puyol after the Spain defender was sidelined for three weeks when he injured his left ankle against Athletic Bilbao on Saturday.
Midfielder Andres Iniesta has played well since his return from injury, while Lionel Messi, Samuel Eto'o and Thierry Henry are expected to play. The trio have combined for 55 of Barcelona's 76 league goals this season.
Barcelona trounced Lyon 3-0 in a group stage match at the Camp Nou last season, although neither team is putting much credence into that result after the French club's strong performance at the Stade de Gerland where Benzema hit the post after nearly scoring.
"Barcelona taught us a lesson and I hope it serves to keep us sharp from the opening minute," Benzema said. "(But) I'm conscious that it will be very difficult to qualify."
Lyon controlled with Juninho scoring from a first half free kick before Barcelona took control in the second half, but managed only Thierry Henry's 69th-minute equalizer.
Lyon, trying to reach the quarterfinals for the first time in three years, will be short-handed against one of the most explosive teams in Europe with John Mensah missing to a hamstring injury, while fellow defender Jean-Alain Boumsong is in doubt with the same injury.
Lyon is also already without defender Anthony Reveilliere (knee), midfielder Fabio Santos (thigh) and forward Sidney Govou (Achilles). Defender Francois Clerc has played just 90 minutes since returning from an opening day knee injury.
Barcelona defender Eric Abidal misses the clash against his former club with a muscle tear in his right leg.
Guardiola and Lyon coach Claude Puel are no strangers either, with the former Barcelona midfielder facing off against Puel's Monaco in the 1993-94 Champions League group stages. Barcelona won both of those matches before eventually succumbing to AC Milan in the final.