Benavidez scored first, charging in behind sharp hooks and forcing Fabiano to cover up. But Fabiano quickly regained his composure and scored with a body kick and some punches. Later in the round, Benavidez backed Fabiano up and fired a barrage of punches.
In the second, Benavidez threatened early with a tight guillotine choke after Fabiano took a weak shot. Fabiano fought free but moments later Benavidez threatened again. Fabiano fought free but less than a minute later, Benavidez tried again and this time got the submission.
Fabiano entered the WEC as a highly touted contender and has gone 4-1 with the promotion. But his upset to Mackens Semerzier last October derailed his title chances.
Benavidez' two career losses both came against current champion Dominick Cruz.