Tsonga ran out of mental and physical energy. Federer just has too much will power, and DelPo's knee didn't help matters.
Errani can play.
What a day, though. I hope tomorrow can offer a little something, Murray-Ferrer ought to be good. Kanepi-Sharapova will be an absolute slugfest, it'll be interesting to see those two on the red stuff.
That Cibulkova line isn't nearly as much fun when you take it in its actual context, but I like it anyways.