The Gunners managed a 2-1 win over Barcelona in the first leg of their Champions League last 16 tie.
Fabregas told ITV: “They don’t lose many games. They are the best side in football’s history in my opinion.
“This is 180 minutes. It’s a nice victory. It will give confidence to the team but that’s all.”
Arsenal were outplayed by the Spanish giants in the Champions League last year.
“First of all we don’t have five or six injured players,” he added.
“Second, we are all one year older. We are mature enough to play big games.
“We showed it here but if we don’t show it (in the second leg in Barcelona) it’s nothing.”
