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Carwin can't afford to gas out against dos Santos at UFC 131.

I’ve always held that it’s hard to blame Shane Carwin for gassing out at UFC 116. Granted it only took Carwin one round to look totally spent against then-champion Brock Lesnar but, man, what a round it was.

Even though each of his previous 12 MMA fights had ended in the first, Carwin probably didn’t expect to put Lesnar in trouble as quickly as he did that night, flooring the champ with a barrage of punches in the early going. Once he got him on the mat … well … having the UFC heavyweight champ down and helpless is likely to induce the kind of sprint it’s difficult (if not impossible) to train for.

And sprint Carwin did. Sensing that he was (literally) within striking distance of the sport’s top prize, he poured it on Lesnar. Carwin threw every punch he had at the champ during that first round, trying to force a stoppage that never came. When the round was through, so was he. The second saw Carwin absent the explosiveness he’d used to ward off Lesnar’s takedown attempts in the first and the former NCAA Division I wrestling champ took the former NCAA Division II wrestling champ to the ground and submitted him in two minutes, 19 seconds.

End result: Instead of celebrating Carwin as the UFC heavyweight champion, we questioned his cardio. Now, as he prepares to step in as a late-notice replacement for Lesnar against Junior dos Santos at UFC 131 next month, those questions seem more relevant than ever.

After all, Carwin may have already been preparing for his own bout on June 11, but it’s been nearly a year since we’ve seen him compete. During that time he had surgery to relieve chronic pain in his neck and back and has judged himself as fit as ever. The cardio, he says, won’t be a problem. It better not be. Though Carwin has been the recipient of some decent underdog money since betting opened last week, dos Santos is still a 2-1 favorite. He also possesses a skill set that will make for a very interesting match-up for the former fulltime engineer.

Like Carwin, dos Santos likes to punch. He thoroughly undressed noted striker Roy Nelson on the feet in his last outing at UFC 117, putting such a beating on the “Ultimate Fighter” winner that it hurt just to watch. Before that he ran through Gabriel Gonzaga and before that Gilbert Yvel. Prior to that – in his third appearance in the Octagon – he broke Mirko CroCop’s orbital bone, causing the MMA legend to concede in the third.

One type of fighter dos Santos has not yet faced in the UFC however, is a dominant wrestler. We know  Carwin has the ability to be just that, but usually prefers to slug it out on the feet. One wonders if that’s really the best strategy against dos Santos. Carwin might be better served to fall back on his grappling, to use his wrestling to grind on the young Brazilian.

It could be the smart choice, but will certinaly also be the more taxing one. To get it done, Carwin will have to be in shape to go the full 15-minutes. 

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