The whole team screwed up against Barca. Sometimes you have to take defeat on the chin and this was one of those times.
I would never use that game as a benchmark for judging a player.
I agree with Tom, to beat Barca you have to play like ****s. Anti football or whatever you want to call it. Jose didnt really worry about anti-football when he lifted the cup last year. It wont be popular but it will work. When we actually knocked them out of the CL it was based on defending.
It also helps if you can keep hold of the ball, which is something United failed to do against Barca. Im sure we will come back stronger next season if we buy some good players.