LAS VEGAS -- After all of the talk and pageantry throughout a wild two-month build to this superfight, former pound-for-pound king Floyd Mayweather and UFC champion Conor McGregor are finally ready to get down to business on Saturday.

Both fighters made weight Friday ahead of their junior middleweight showdown, which is expected to challenge pay-per-view and live gate records for combat sports. You can watch Mayweather-McGregor live on Showtime PPV.

Mayweather (49-0, 26 KOs) weighed in at 149.5 pounds -- well under the 154-pound limit -- while McGregor, who is making his pro boxing debut, came in at 153 pounds. Mayweather, 40, who returns Saturday from a two-year retirement, further cemented his prediction from days earlier that he would close his career with a knockout.

"It won't go the distance, mark my words," he said. 

McGregor (21-3 in MMA), who has held titles in UFC at 145 and 155 pounds, shot down talk from Mayweather that he had trouble cutting weight during fight week.

"[Mayweather] looks like dog shit, you know that," McGregor said. "He looks blown up, full of water. He's not going to keep my pace. Trust me on that. That's the worst shape I've ever seen him. He looks blown out, out of shape. I'm going to breeze through him. Trust me on that.

"[Weighing in at] 153, I'm a professional. I make weight. It's sacrifice, it's dedication, it's focus. But I make it, and that's it. Look at me. I'm in peak physical condition. I put in the work -- as everyone can tell."

While Mayweather will only be a few pounds heavier on Saturday night, McGregor is expected to rehydrate and balloon up as much as 20 pounds before the fight. The UFC champion told Jim Gray as much after stepping off the scale.

"[I'm going to be] a lot bigger. A lot bigger than him," McGregor said. "I'd say close to 170 [pounds]."

McGregor, 29, screamed in the face of the stoic Mayweather during the traditional face off after both fighters stepped off the scale.

"I've been here before. I know what it takes to win a fight of this magnitude," Mayweather said. "I do a lot of [talking]. He did a lot of [talking]. But tomorrow, it comes down to the fighters."

Despite McGregor's insults, Mayweather looked fit and strong on the scale. The longtime welterweight came in nearly 5 pounds under the limit.

"Weight doesn't win fights, fighting wins fights," said Mayweather, who previously announced he promised his family he would retire for good after Saturday.

"I'm not really worried about the scale or the last time. This will be Conor McGregor's last fight also. The fans can't fight for him. It comes down to the two competitors. The fans can't fight for you. All 49 times I went out there, it was one-on-one."

The crowd inside T-Mobile Arena was decidedly pro-McGregor with a large section of Irish fans screaming "pay your taxes" at Mayweather throughout the weigh-in.

"There's a saying: You'll never beat the Irish," McGregor said. "And that's it. You can't beat us. We roll in, and we take over wherever we want. Las Vegas is Ireland now."

McGregor concluded by brushing off the concept of being overmatched in the fight. "I'll stomp my foot right in the center of that ring. I won't go nowhere other than the center of that ring. So let's go, let's see who can take it."

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