Alves - best defender on the pitch, but some wayward passes (Pique would be second)
Messi - Opportunistic goal, good assist for Cesc's goal, but loads of mistakes and definitely not among his best games
Thiago - comes in and scores a goal
Honourable mentions:
Fabregas - scores a great goal and was close to getting on the end of a couple of passes that would've seen him alone with the gk, often looked dangerous but won't make the top three seeing as he should have been shown a red card for a late tackle early in the second half.
Busquets - one poor pass early on could have been dangerous, lost the ball some times but usually showed great skill and composure
Iniesta - fantastic dribbling and interplay but his passing wasn't up to his usual standards
Piqué - had a solid game in defense
Xavi - anonymous but composed, didn't participate enough offensively