Pep Guardiola admits Barcelona need to find way to break Chelsea down after a 1-0 defeat in their UEFA Champions League semi-final first-leg at Stamford Bridge.
Chelsea took the lead on the stroke of half-time through Didier Drogba, and they held out to take a narrow advantage into the second-leg next week.
Barca hit the post late on through Pedro and missed a number of chances, but Guardiola admits they will need to work hard to break down the Premier League outfit.
"When they put 10 inside the area it's not easy, then on the only counter attack they had they scored a goal," said Guardiola.
"It's the kind of challenge that you get in the semi-finals of the Champions League - we accept that and we will try to overcome it.
"We must try to find other ways to generate chances. They defend very deep and we must try to find some inspiration and have lots of patience. But we created lots of chances.
"We must try to have 24 chances again and score a goal. We must create a lot to get a goal. We lost despite those numbers - Chelsea had that luck we didn't have.
"We are trying to find the secret to creating more chances, but I am not here to say if I agree or not with their style of play. They are a team with a lot of experience and it is not easy to play at Stamford Bridge.
"Both teams are strong, but we play better. We'll see what happens next Tuesday."