LAS VEGAS – HBO will offer a broadcast of Lewis-Rahman II this Saturday. Here’s two things you should know going in: Don’t plan to be watching long. And there will be no need for Lewis-Rahman III.

In answering questions about his heart and his focus, if not his chin, Lewis reclaimed the heavyweight championship for a third time with a fourth-round knockout over an overwhelmed Rahman Saturday night at the Mandalay Bay Events Center.

It was a perfect fight for Lewis, one that will reclaim the box-office appeal he had prior to Lewis-Rahman I.

He showed poise, flashing a confident grin when Rahman tried to enter his dressing room before the fight to observe the taping of his hands. Rahman wasn’t allowed in.

He showed patience, waiting until the second round to feature the jab, and then the third round to counter off of it. The knockout punch, in the fourth, was not an aggressive charge, but the result of a grazing left hook, right-hand combination.

He also showed power, collecting one of the most brutal knockouts of the year. The right-handed Rahman stopped Lewis in South Africa last April with a terrific punch that turned Lewis’ legs to spaghetti. But Lewis’ punch, Saturday night, sent Rahman timbering like a falling tree. The sound of his head bouncing off the canvas was like a bowling ball hitting concrete.

Lewis looked genuinely joyful and relieved at his post-fight press conference. Though he wore his customary sunglasses, his self-satisfaction was evident. His dominating win had sent Rahman to the hospital for a mandatory examination, and it also put him back atop the heavyweight division.

“Has Been Rahman. I changed his name,” said Lewis, who reclaimed the WBC, IBF and IBO belts with the victory. “He’s the Buster Douglas of the 21st century. I told you that punch was a lucky punch in South Africa. I’ve got too many attributes for him.”

A showdown with Mike Tyson seems inevitable, though Lewis (39-2 with 30 KOs) isn’t about to beg. “After he fought that blimp (Brien Nielsen), he said he still needed two more fights (to get ready for Lewis),” Lewis said. “When is he going to be ready? If not him, there’s other guys out there that deserve a chance.”

Rahman (35-3, 29 KOs) seems to have made the most of his chance. He reportedly made almost $10 million Saturday night, a purse that seemed unimaginable when he was a 20-1 underdog in their first fight last April. But if Oliver McCall, who knocked out Henry Akinwande in the 10th round of their fight on the undercard Saturday, can come back, Rahman certainly can.

“He hit me with a good shot and I couldn’t recover,” Rahman said. “Any one of us can get beaten on any given day because there isn’t a dominating heavyweight champion.”

Lewis, 36, would beg to differ. He becomes just the third man to win the heavyweight title three times. The other two are Muhammad Ali and Evander Holyfield. He also became the fourth fighter to regain the title from the man who beat him. The others were Floyd Patterson, Ali and Holyfield.