Former middleweight champion Anderson Silva marks his return to the Ultimate Fighting Championship on Saturday night against Nick Diaz at MGM Grand in Las Vegas, after Silva spent a year recovering from a gruesome broken left leg suffered in the same arena in December 2013.
This non-title middleweight main event is scheduled for five rounds.
Silva, at 39, has rebuilt the strength in his left leg that needed a steel rod inserted to help it heal after a second consecutive title loss to Chris Weidman. The unanswered question is: how will Silva's leg respond to the contact the 31-year-old Diaz plans to deliver?
Diaz is a great unknown. The jujitsu schooled former Strikeforce champion and ex-UFC welterweight title contender lobbied hard for the fight, then failed to show up at a public workout Wednesday.
The last time he fought in Nevada, Diaz submitted a positive post-fight test for marijuana.
Yet, there's no doubting Diaz's ability and ring smarts to do anything to win a fight, and he says the move up in weight and a layoff of nearly 22 months since losing the welterweight title shot against Georges St-Pierre are positives.
"If you fight three times a year, it's hard," Diaz said in a recent conference call. "I've never had a year off. So I came out more to my potential, as far as athleticism and strength. … My strength is being more versatile."
Said Silva: "Nick is dangerous. But this is a sport, not a street fight."
Actually, MMA can be both, depending on who can impose their will.
So the doubts about Silva's leg persist.
The Brazilian had them, too, after Weidman blocked that second-round kick 13-plus months ago, rendering Silva's leg to something that resembled Jell-O. The former champion crumpled to the canvas, screaming in agony.
Has he seen a replay, someone asked.
"I see, but I don't talk more about this," Silva said.
"My leg's good and I'm very excited for the fight. When I go walk to the octagon, it feels like the first time, like my first fight in the UFC."
Silva said after returning home to Brazil from a lengthy Las Vegas hospital stay that included some physical therapy, he was frightened to test the leg in training.
"How's your leg?" a coach asked him in Brazil.
"I don't know," Silva answered. "I'm scared for training."
Silva said he saw his friends doing jumping drills and decided to give it a try.
The coach watched Silva's jumping and pushed him: "Finish, go train, your leg [has] nothing more" to recover from.
Now comes the test for all to see in a fight against Diaz that Silva, who was middleweight champ for seven years, believes will turn into a "martial arts test."
Silva is clearly relaxed, much of that having to do with the layoff that allowed him his first stretch of more than three months of uninterrupted time with his family in 11 years, he said.
He also has a new perspective on the UFC belt, something he possessed so long it became hum-drum to think of any fight as just another title defense.
Silva effusively thanked his manager, Ed Soares, for reminding reporters that "Spider" is still the No. 1-ranked middleweight, but it was his appreciation for where he's at in life that shines.
"I fight for the UFC, my family," Silva said. "I don't know if I'll have another chance for the belt. Whether I have the chance or no chance, I'm happy to be back."