Anderson Silva’s UFC cloak of invincibility is slipping

Anderson Silva doesn’t say much to reporters, letting his interpreter-manager be more expansive.

The long-reigning middleweight champion of the Ultimate Fighting Championship can afford such comforts while riding a 12-0 record in the organization dating to 2006, but like his invincibility, tolerance with such smugness is slipping away.

Silva, 35, faces his former training partner and former UFC champion Vitor Belfort, 33, in the main event of the UFC pay-per-view card Saturday night at Mandalay Bay Events Center in Las Vegas.

And if the champion fights anything like he did in his near-loss to Chael Sonnen in August, we might have a new person wearing the belt.

“Every fight’s different,” the Brazilian Silva said, according to his manager Ed Soares. “Nothing changed after Chael, it’s the same way I always feel going in there. I injured my ribs before that fight. I feel great now, happy to be here.”

A nearly 3-to-1 underdog in Las Vegas sports books, Belfort (19-8) has won almost half his fights by submission. He is taking a philosophical approach to fighting Silva after overcoming a past release by the UFC, a positive steroid test and a shoulder injury that forced him to withdraw from a scheduled title fight last February against the champion.

“The only one who is unbeatable is God,” Belfort said. “The rest of us are beatable. I know he’s a great fighter, but I’m focused. Whoever’s in front of me now is going to be in a war.”

Translation: Belfort watched Silva (27-4) get pummeled by Sonnen through four rounds in the Oakland fight, which ended in the fifth round with Silva pulling off a stunning submission to salvage his belt.

Sonnen’s performance was stained by his positive test for a performance-enhancing substance, but the shocking sight of Silva in trouble has changed things.

“He knows he’s facing a big challenge now, even if he’s trying to hide it,” Belfort said. “I know he’s got butterflies in his belly. I’m going there to win.”

The Super Bowl weekend card includes two other compelling fights, as former middleweight champion Rich Franklin fights former light-heavyweight champion Forrest Griffin, and rising-star light heavyweights Jon Jones and former Arizona State wrestler Ryan Bader meet in what could be the most action-packed bout of the night.

lance.pugmire@latimes.com

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