Junto Nakatani is a bad, bad man.

In his third fight at 118 pounds, the WBC bantamweight titleholder proved to be too strong, too powerful and simply too clever for Thai veteran Tasana Salapat (AKA Petch CP Freshmart) in their all-southpaw battle at the Ariake Arena in Tokyo, Japan on Monday night.

Salapat, a veteran of 77 fights with just one loss on his ledger, had never previously been stopped. That changed tonight when he was stopped in six rounds by Nakatani, currently rated at No. 9 by The Ring at pound-for-pound.

In his first fight abroad, the 30-year-old Salapat knew he was in for a fight from the opening bell when a sweeping left cross from Nakatani buckled his legs in the opening frame.

Like most Thais, Salapat was tough and determined. He pressed the action and tried to drag Nakatani into a firefight. But the rangy five-foot-eight Japanese boxer kept him at range, encouraging him to come forward so that he could walk him into counter shots.

A left-hand counter from Nakatani in the second round gave Salapat a taste of what was to come.

Nakatani dictated the pace from range, upping the tempo round after round as he made the Thai reach while looking to land a killer blow.

Sensing he was behind, Salapat lifted his work rate in the fourth. That was fine in theory, but it only opened up opportunities for Nakatani to land his own hard countershots. The titleholder remained composed and economical under the incoming fire, picking off his opponent at will.

Things opened up in the fifth with both boxers exchanging on the inside. Salapat was the busier of the two, but the heavier blows came from the Rudy Hernandez-trained Nakatani, who showed great defense to roll under incoming fire and shoot back with hard shots of his own.

In the sixth, Salapat came out firing. Nakatani stood his ground and weathered the storm. A two-fisted salvo from the champion bludgeoned the challenger to the canvas. Salapat beat the count, but was only a matter of time.

A crunching left cross to the jaw crumpled the Thai to the canvas just before the bell. Referee Laurence Cole called a halt to the contest with just one second left in the round.

It was another dominant victory for Nakatani, who proved once again why he is rated at No.1 by The Ring at bantamweight.

The victory sees Nakatani lift his record to 29-0 with 22 knockouts. Salapat drops to 76-2 with 53 knockouts.

In the semi-main event, ex-kickboxer Tenshin Nasukawa continued his unbeaten run under the Queensberry Rules.

Nasukawa, 26, was largely untroubled by 23-year-old Filipino Gerwin Asilo in their 10-round bantamweight bout. The Japanese southpaw suffered a small cut over the left eyebrow but otherwise cruised to victory in his 97-92, 98-91 and 98-91 win.

The always-popular Nasukawa lifts his ledger to 5-0 with two knockouts, while Asilo sees the first blemish on his resume, falling to 9-1 with 4 knockouts.