I think Diaz is competitive for a while, since he is fast enough on his feet to crowd Crawford and land a few flurries. But the more the fights goes on, the more Crawford skills and poise prevails.
Yeah, I think that's true at 135. Diaz holds his own for the first half of the fight, but at a certain point, Crawford starts to pick him apart. At 140 it's a just a blow out and Diaz doesn't see the late rounds. Diaz was getting wobbled by Paulie at 140 for Christ sake.
Diaz lasting the distance at 135 depends on whether or not he becomes a "good boy". Let's not forget, Diaz did have some bitch in him. If he's content on survival, then I think he goes the distance and loses a wide UD. If he keeps going all out, then I think Crawford eventually counters him with something big that ends the fight.