Kenshiro Teraji barely retained his WBA and WBC light flyweight titles Tuesday, while fellow Japanese boxer Seigo Yuri Akui took the WBA flyweight belt from his previously undefeated Ukrainian opponent.
Teraji won a majority decision over Venezuela's Carlos Canizales after a slugfest at Edion Arena Osaka, where the two fighters traded knockdowns in the early rounds.
Canizales stepped up the pressure toward the end of the bout as Teraji moved around the ring in the last two rounds to avoid being trapped against the ropes.
Two judges scored the fight 114-112 in favor of Teraji, while the other had it 113-113.
"I'm so relieved," said Teraji, who improved his win-loss record to 23-1 with 14 knockouts. "Canizales was a tough fighter. I just gave it my all."
"I couldn't fight inside late in the match. I had to keep him at a distance with jabs. That wasn't what I wanted to do, so it's a bit frustrating. I learned many lessons from this fight. I'll come back stronger."
Canizales, the top-ranked challenger, fell to 26-2 with 19 KOs and one draw.
Earlier, Akui defeated Artem Dalakian by unanimous decision in his first world title bout. Judges scored their fight 116-112, 117-111, 119-109.
Akui looked more aggressive than the Ukrainian, who showed great footwork but failed to land enough effective shots.
In a non-title eight-rounder, Tenshin Nasukawa, in his third match as a professional after an undefeated kickboxing career, won when Mexico's Luis Robles retired after three rounds.