Chelsea midfielder Cesc Fabregas says his teammates must improve in the Champions League if they are to reach the level of Barcelona.
Fabregas spent three years at Camp Nou before moving to Stamford Bridge last June, and will line up against his old club in the final match of Chelsea's three-match American tour on Wednesday.
The Champions League is one of the few honours to have eluded Fabregas in a glittering career at club and international level.
Chelsea were eliminated from last season's Champions League in the last 16 by Paris Saint-Germain, and Fabregas said: "I always say that the Champions League was the one disappointment from last season.
"I gave the team a seven or an eight out of 10 for the year, but to complete a top, top season, we needed to do better in the Champions League.
"Unfortunately we went out in the last 16 on away goals, we didn't actually lose the game. But we do have to play better in the Champions League this season."
Lionel Messi and Neymar are being rested by Barcelona during pre-season, and Fabregas is confident Chelsea have the firepower to compete with the Spanish and European champions.
"It is nice to play against [Barcelona]. I spent beautiful years there, some of the most beautiful moments of my career and my life personally as well. It will be great to play against them again," he added.
"I think they are the best team in the world, especially when the front three are on form. I don't remember a front three in Messi, [Luis] Suarez and Neymar as powerful and talented as those three since I was born. Obviously they are a threat to everybody in the competition again this season.
"We won't be playing against Messi and Neymar in this game, so we are a bit lucky because of that. But if we want to win Champions Leagues, we have to compete against the best. We will have to do well."
