It’s not easy to score a third-round knockout that also qualifies as a come-from-behind knockout, but that’s what Shokuchi Iwata did in the first of the four alphabet title fights — among seven such fights across a two-day festival — Sunday from Ariake Arena in Tokyo, Japan.

Iwata, from Tokyo, lost the first two rounds and was on his way to losing the third as well against Spaniard Jairo Noriega, before scoring two knockdowns late in the stanza and claiming the vacant WBO light flyweight belt at the 2:59 mark.

The 31-year-old Noriega, unbeaten and fighting for a major belt for the first time, used his jitterbug energy and frequent lead power shots — mostly left hooks and left uppercuts — to take charge at the outset. Iwata, 28, calmly worked behind his jab and tried to wait Noriega out, as it seemed unlikely his opponent could keep up that pace for 12 rounds.

Nothing changed for the first 2½ minutes of round 3, but inside the final 30 seconds, Iwata landed a sudden right uppercut that stunned Noriega. He followed with another right uppercut to the cheek to begin a combination that put the visiting fighter down. Noriega beat referee Raul Caiz Jr.’s count and had just 10 seconds to survive before the bell, but as that bell rang, Iwata landed a crushing left hook to the chin to floor Noriega, 14-1 (3 KOs), again, and Caiz waved it off without a count.

Iwata, 14-1 (11 KOs), having scored his fifth straight KO since a 2022 decision loss to Jonathan Gonzalez in his only previous title try, said afterward that he’d planned to retire if he’d lost this fight. He proceeded to call out fellow 108-pound beltholder Masamichi Yabuki of Nagoya, Japan, who knocked out Sivenathi Nontshinga to claim a title just a day earlier.

Iwata’s countryman, Seigo Yuri Akui, was made to work considerably harder and longer in the next bout on the card, his second defense of the WBA flyweight title. After 12 tough rounds against Thai challenger Thananchai Charunphak, Akui was awarded a split decision by scores of 115-113 from Robert Hoyle and 117-111 from Kwan-Ho Jang, against a 115-113 card for Charunphak from Guillermo Perez. Boxing Scene favored Akui, 116-112.

The so-called “championship rounds” were critical, with Akui, 21-2-1 (11 KOs), appearing to win the 11th and 12th decisively to separate himself. It was an impressive response to the challenger’s best round of the fight in the 10th, when Charunphak, 25-2 (15 KOs), appeared to hurt Akui with a relentless body attack.

The fight was competitive throughout and there was rarely a dull moment. From the outset, the 29-year-old Akui was moving forward and pursuing, while Charunphak, 24, was mostly on his toes, circling and jabbing — but stopping periodically to step in and pop stiff shots. Both boxers kept up diligent body attacks, with Charunphak probably doing the more effective work on that front.

Akui got a thumbs up from his young daughter at ringside after the fourth round, and indeed, her dad seemed in control for much of the first half of the bout. But Charunphak kept raising his arms after every round, and he raised his game as well from round seven to 10, doing the aggressive work that would help put him ahead on one of the three cards.

Charunphak suffered his first defeat since losing his second pro fight. For Akui, this was his ninth straight victory.