Diaz doesnt hit hard ??? Ask Robbie Lawler that one. This will be real simple after about 20 seconds Koscheck wont want any standup with Diaz or he get knocked the f out. He will go for the takedowns. Diaz has almost BJ Penn like jiu Jitsu and could control from the ground enough to nulify CockCheck.
Anyone could win but i think Diaz by Submission.