Barcelona boss Ernesto Valverde has warned victory over Lyon in the second leg of their last-16 Champions League tie is no formality.

Valverde's side are big favourites after squandering a hatful of chances when they were held to a goalless draw in France three weeks ago.

But following shock wins last week for Manchester United and Ajax against big guns Paris St Germain and Real Madrid respectively, Valverde is taking nothing for granted.

"Nil-nil from the first leg is a result which benefits neither side because if neither of us score it will go into extra time," Valverde told a press conference.

"Lyon will come here with their weapons, they've got a very strong attack – very quick, powerful players up front and I'm sure they'll try to exploit that.

"They know how important it would be for them to get an away goal tomorrow, so I'm sure they'll look for that too."

Barca made a surprise quarter-final exit last season after being knocked out by Roma and while Valverde said that was of little concern, he admitted last week's upsets proved there are no easy games in the knockout stages.

"Look, we're not worrying too much about what happened a year ago, we've spoken enough about that. We're just worried about tomorrow's game," Valverde said.

"Last year happened. The other Champions League games are very important to appreciate what the other teams are like and it's a reminder that there are no small teams.

"Also, the result of the first leg does not always matter that much. You've seen some big turnarounds in the games last week.

"But in our case it's a very balanced result from the first leg. We have to win tomorrow if we want to qualify."

Valverde confirmed Ousmane Dembele will be assessed but he remains a big doubt after sustaining a hamstring injury in Saturday's home win against Rayo Vallecano, which kept Barca seven points clear at the top of LaLiga.

Lyon captain Nabil Fekir missed the first leg through suspension and said he had been counting down the days for Wednesday's return fixture.

"Barcelona are one of the best teams in Europe," the France international told Lyon's official website.

"It's always fun to play against these kinds of teams and it's normal that the fans expect a lot from me in this match. We will give our all. Even if we know that it's going to be a tough match."

Lyon let slip a two-goal lead at Strasbourg on Saturday and lie third in Ligue 1, seven points behind second-placed Lille and 21 adrift of runaway leaders PSG.