The Dutch goalkeeper has now played his last match before retiring, but was possibly at fault as he failed to reach Lionel Messi's long-range strike, which gave Barcelona a 2-1 lead on the night.
When asked about his final competitive match, Van der Sar said he was unaware whether he was to blame for Messi's strike, but believed mistakes made by the whole team were the reason United had lost the match.
“We made one or two mistakes, and they punish you," he told reporters after the match.
"It was one game too many for us I think. It’s not nice to lose of course, but they had the better chances.
“I don’t know if I could have prevented Messi’s goal. I thought I was positioned well, but I think Villa was blocking my sight. Messi tends to curl it to the far post, and he just clipped it around Villa.
“They are very good. We started well in the first 15 minutes, same as we did in Rome, and you just have to try and score the first goal but we didn’t do that.”
Van der Sar has had an illustrious career which has seen him win every major club trophy in the game.
Despite a disappointing outcome in his last outing, he looked back on his career with a great deal of pride.
He added: "It’s not always given that your career ends on a good note, but I thank everybody for the memories and we’ll see each other again."
His last manager, Sir Alex Ferguson, spoke highly of the Dutchman as he now looks to trying to fill his considerable presence in goal for next season.
He said: "Edwin has been a fantastic servant to Manchester United, we wish him well.
"He’s had a fantastic career and he’s had that great career with tremendous honour and I think that’s the thing that stands out about him."