Maybe that's why he wasn't playing well. According to Paul Coro's blog, Barbosa had elbow surgery last week. A quote from Leandro Barbosa's brother said that he was in a lot of pain after game 1 of the Lakers series and throughout the rest of the playoffs but they didn't want to say anything and give something away to the Lakers or the Spurs.
I don't think this was the type of "freak" injury the Suns had had the previous two seasons but if it really did affect Barbosa, at least it explains why he wasn't playing as well as we thought he was capable of.