Neither of them. Guzman whoops Arthur easy, and Guerrero is too much for china chin Litzau....but for the sake of the topic. I'd say Litzau has a better chance to pull the upset.
Litzau. Guerrero is good, but nothing special, and if Litzau would keep keep is hands up he could be a very good fighter. His chin isnt bad, its average, its just that his defense is so bad.
All I'm saying is Arthur has absloutley no chance of winning unfortunately. Guzman is on another level.