UFC 137 main-card results: Diaz retires Penn, Nelson retires ‘Cro Cop’

LAS VEGAS – All Nick Diaz needed was the taste of blood.

The former Strikeforce champion, who infamously cost himself a title shot with Georges St-Pierre when he skipped pre-event media commitments, instead took out his frustrations on B.J. Penn and b…

LAS VEGAS – All Nick Diaz needed was the taste of blood.

The former Strikeforce champion, who infamously cost himself a title shot with Georges St-Pierre when he skipped pre-event media commitments, instead took out his frustrations on B.J. Penn and battered the former UFC champ into the night’s second career retirement.

The fight headlined the pay-per-view main card of Saturday’s UFC 137 event, which took place Saturday at the Mandalay Bay Events Center in Las Vegas.