Nathan Palmer and Juan Carlos Pelayo scored the fight 116-111, while David Sutherland had it closer at 114-113 but Inoue (23-2, 5 KOs) proved a worthy main event winner at Toyota Arena in Tokyo, Japan.

The victory was even sweeter given Nasukawa's adjustments and measured output, besides a blistering burst culminating with a seventh-round knockdown. It was a fight-shifting moment he couldn't capitalise on.

Inoue was noticeably twitchy during the opening exchanges, no doubt eager to punish any defensive lapses as the Tokyo southpaw opposite him purposely boxed on the back foot.

Not for the last time, veteran referee Michael Griffin ruled no knockdown in the second stanza after Nasukawa (8-2, 3 KOs) appeared to floor the champion. A tangle of legs it was, as they often closed the distance — which favored Inoue.

Fleet-footed and the better mover, Inoue punished Nasukawa's tendency to wait for openings by tagging him with jabs and making him miss. Nasukawa would connect on a straight right hand to head and body, then miss badly with a series of wild hooks.

That was the clearest indication that he hadn't found his range after four rounds, as Inoue clubbed him in the pocket and left him temporarily unsteady. The scorecards through 12 minutes were in the champion's favor and a less lenient official would've credited him with a knockdown in the fifth.

Outworking the challenger, he often flicked two-punch combinations and would time his exits nicely while keeping the distance relatively short. Nasukawa complained plenty about rough-housing in the clinch and tried officiating himself at times when he would've been better served to accelerate forward with purposeful output.

Defying those teething problems, he suddenly landed a stinging left hand to floor Inoue at the start of round seven. He dug downstairs, rocked the 30-year-old against the ropes, waded into danger as Inoue waved him forward and the optics were anything but comfortable.

Yet that was as good as it got for Nasukawa, unable to truly chain together much more in the way of damaging sequences as Inoue settled in the eighth and pulled away behind his boxing skill. Nasukawa didn't stop trying and closed the gap, but fell short again as Inoue completed his second championship defense.

His older brother and The Ring's No. 1 pound-for-pound fighter Naoya spoke highly about his sibling's improvements in the build-up to this marquee matchup, which we've seen yet again on the world stage.

Start as you mean to go on. Sam Goodman's aggressive nature took Ryosuke Nishida by surprise and he used that momentum to produce a career-best decision win, claiming the IBF interim junior featherweight crown.

Nicolas Esnault's 116-109 scorecard was widest of the three judges and didn't tell the full story from a pulsating 122-pound tussle, one neither wanted to lose.

Ellis Johnson (115-110) and Patrick Morley (114-111) had it closer, reinforcing just how competitive Nishida was throughout, despite conceding the edge in punch power and relinquishing two points.

He was deducted one in the eighth and another two rounds later for persistent low blows, after a bemused Goodman (23-1, 8 KOs) had one chalked off for leading with his head moments earlier. That spurred him ahead to continue swinging with bad intentions, as both were wearing the damage from a bruising battle after 36 minutes.

Goodman reaffirmed a desire to face the world's best after an impressive showing away from home, having learned lessons having fallen short in the weight division above against then-WBA champion Nick Ball.

"I'm feeling unbelievable, a lifetime of work, this [title] ain't just mine, it's for everyone who supported me. We ain't stopping here, I love Japan but here to compete with the best of them, Nishida's a tough champion and brought the best out of me. I can't wait to fight here again, felt at home, I welcome all challenges ... bring them all on."