Floyd Mayweather ended what developed into a firefight in the second round of their three-round exhibition by stopping Japanese mixed martial artist Mikuru Asakura at the end of that round Sunday in Saitama, Japan.

The 45-year-old Mayweather dropped Asakura just before the bell sounded to end the second round. He tried to get up, but the southpaw couldn’t quite beat referee Kenny Bayless’ count before it reached 10.

Mayweather won in the main event of a Rizin pay-per-view show at Saitama Super Arena.

The 30-year-old Asakura, who is 16-3 in MMA matches, competed in a boxing match, albeit an exhibition, for the first time.

Mayweather was in complete control of the second round until Asakura clipped Mayweather with a right hook with just over 45 seconds to go in the second round. Asakura landed a left several seconds later, which made Mayweather smile at him as he moved backward.

Bayless warned Mayweather for a low blow with just under 20 seconds left in the second round.

Mayweather then landed two right hands as the second round moved toward a conclusion. Another right hand by Mayweather made Asakura fall to the canvas and roll over just before the bell sounded to end the second round.

Asakura struggled to get to his feet as Bayless counted. Bayless counted to 10 just as Asakura got off the canvas and the American referee waved an end to the action.

A straight right hand by Mayweather landed with exactly a minute remaining in the second round.

Mayweather lunged forward and caught Asakura with a right hand with 1:50 remaining in the second round. He hit Asakura with a right to the body just after the halfway point of the second round as well.

Mayweather nailed Asakura with a right hand 40 seconds into the second round.

Mayweather went on the offensive in the final minute of the first round. He had difficulty catching Asakura with clean punches, though, and appeared to lose it.

Asakura backed Mayweather into the ropes with just over 1:20 on the clock in the first round, but Mayweather blocked his punches. Asakura landed a hard left to the body a little less than a minute into the first round, which emerged as .

Manny Pacquiao, the retired legend who lost to Mayweather in the most lucrative boxing event in the sport’s history seven years ago, attended the show. The Philippines’ Pacquiao, who is expected to participate in exhibitions as well, walked to the ring and addressed the crowd before Mayweather squared off against Asakura.

Their exhibition headlined a mostly mixed martial arts event Sunday afternoon at an arena just north of Tokyo. It aired as a pay-per-view main event Saturday night in the United States.

Mayweather, who resides in the Las Vegas area, was inducted into the International Boxing Hall of Fame in June. He ended his 21-year pro boxing career undefeated (50-0, 27 KOs), won world titles in five divisions and made more money in purses than anyone in the history of the sport.

While Mayweather won, Asakura lasted a lot longer than Mayweather’s prior opponent in Japan.

The Grand Rapids, Michigan, native needed less than three minutes to knock out Tenshin Nasukawa in an exhibition that was scheduled for three rounds in December 2018. Mayweather dropped Nasukawa, who was much smaller than Mayweather, three times in the first round before their bout was stopped at Saitama Super Arena.

Mayweather’s win against Asakura was his fourth in exhibitions since he retired from professional boxing following his 10th-round stoppage of UFC superstar Conor McGregor in a 12-round, 154-pound boxing match in August 2017 at T-Mobile Arena in Las Vegas. Mayweather hasn’t fought an experienced boxer in seven years, not since he out-pointed former WBC welterweight champion Andre Berto in September 2015 at MGM Grand Garden Arena in Las Vegas.

In the exhibition bout before Mayweather’s win, the superstar’s bodyguard, Ray Vinci Sadeghi, was knocked down twice early in the third round of their boxing match and stopped by Kouzi Tanaka, a 33-year-old kickboxer.

Japan’s Tanaka caught Sadeghi, a native Iranian who goes by the nickname “Jizzy Mack,” with a left hook barely five seconds into the third round. The 40-year-old Sadeghi went down, but he rolled over, answered the count and tried to fight out of the trouble.

Tanaka cracked him with another left hook that made him stumble and fall face-first to the canvas 50 seconds into the third round. Their scheduled three-rounder was stopped as soon as Sadeghi went down for the second time.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.