The Blues go into Tuesday's Champions League semi-final second leg with a one-goal lead.
However, the Dutch goalkeeper has blasted the West London club, claiming that they were lucky in the first leg.
"For the sake of the game and for football in general, I hope Barcelona win in the Nou Camp," said the former Manchester United star.
"I love teams who attack. Chelsea did nothing but defend with nine players and kept lots of players in the middle of the park. But this tie could have been over by now.
"I expected Chelsea to lose by a big figure. And it could still have been 5-1 to Barca at the end. Chelsea had just one shot at goal – and they scored."
Van der Sar retired from football last season.