This fight totally slipped by me and it's happening in a couple weeks! Awesome fight, but I honestly believe MJ has the best boxing in the division and provided he's able to avoid the ground at all costs, which he's really good at doing, he should be able to pick Diaz apart standing. They're both southpaws so that will open up the leg kicks for Johnson too (Diaz bros. don't believe in checking kicks) to supplement the hands.
That being said, if Nate has rediscovered his motivation, this could turn out a wee bit differently.