Sakura really surprised me when she decked Sai; I mean, I know she's got a temper, but seeing her absolutely whale on him for badmouthing Sasuke showed just how deep her loyalty still runs, even after everything. It's almost like she was channeling Tsunade's strength, defending her teammates no matter what. I can't help but wonder if part of that fury was also for all the pain Sasuke caused them, now focused outwards.