I'll argue that if Szymd didn't have his mechanical today, that Basso would have had a grind train for another 3 km up the Passo Giao. This would likely have dropped two to three more of the leading 6 off before the top. Clearly Uran was just on his edge through the latter half of the climb. Scarponi wasn't looking too hot for quite a while (was looking at Hesjedal with a WTF expression). I'd say that the other rider who was on the edge from time to time was Rodriguez.
Extend this on to Friday and Saturday, giving Szymd a bike that continues to work and then it is Basso and Hesjedal grinding, with Pozzo sprinting at the top. Everything could depend on the day though. The steeper grades will favour some of the pocket rockets though.
This of course, will be wrong and Rujano will do a 50km break with Nieve, to be caught by the Team Sky TTT setting up Mark Cavemiazov for an uphill mountain sprint win over Ferrari, who is disqualified for dangerous downhill cornering.