I'm really torn between Nishikori and Clayray, but I think it should go to 3 sets. If Kei plays like he did today I give him a slight advantage. Although Murray's defense will definitely test his attacking capabilities.
Nishikori can win this, I would favor him more to beat Nadal if they meet in the final. Murray tends to choke and though we are seeing a lot of Clayray 3.0, he often reverts to his base form and folds against top players.