• UFC 137

Diaz knows he can't get the job done - Sonnen

Chael Sonnen believes Nick Diaz showed weakness in the lead-up to UFC 137 by attempting to lure BJ Penn into a five-round encounter.

Diaz v Penn was bumped to main event status after the withdrawal of Georges St-Pierre from his welterweight title bout with Carlos Condit. As a result, the card is left without the five-rounder that it initially expected.

The Diaz camp issued a challenge to Penn last week, with Cesar Gracie saying his man could go 25 minutes. Sonnen sees that as a ploy from Diaz to lure Penn into a longer fight, knowing the Prodigy has tired significantly in previous clashes with St-Pierre and Jon Fitch.

"Let's not miss what's really happening here. If you're a Diaz fan, you've got to swallow real hard when he tries to change the parameters that have already been agreed," Sonnen said on ESPN's MMA Live.

"What he effectively did was come out and say, 'Look, I can't get the job done in 15 minutes. Let's change the agreement'. BJ Penn then says, 'Hey, I've got no problem with it - I can put you away in 15 minutes.'

"The third angle to this is as a fan. Listen guys, I want to see you compete but you're getting 15 minutes of my time and that's it. After three rounds, fade to black, roll the credits, I've got other things to do."

Kenny Florian, who has lost to Penn in the past, is adamant the fight will not be changed to a five-rounder, insisting it is simply wrong to ask individuals to change at the last minute.

"It's only 11 days out before this fight's going to take place - it's not going to be a five-round fight and it shouldn't be. These guys have already agreed to a three-round fight," Florian said.

"They're not going to change the way they've been training because it is a big difference. Training for a three-round fight and training for a five-round fight is completely different. Your strength and conditioning, the amount of rounds you're sparring, who you're bringing for those sessions - it's completely different."

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