Japanese boxing brothers Yudai and Ginjiro Shigeoka both won by knockout in a world minimumweight interim title doubleheader on Sunday.
Ginjiro, the younger of the two, became IBF interim champ with a ninth-round knockout of the Philippines' Rene Mark Cuarto at Tokyo's Yoyogi 2nd Gymnasium before his older brother knocked out Puerto Rico's Wilfredo Mendez for the interim WBC title.
Ginjiro is the IBF's fourth-ranked contender and hit the canvas in the first round, but recovered to knock the third-ranked Cuarto down in the seventh and twice more in the ninth.
He said he was relieved to have gotten his job done, with the bout falling on the seventh anniversary of the main tremor of a series of deadly earthquakes that ravaged their native Kumamoto Prefecture.
"I went into the ring determined to deliver smiles (to the people of Kumamoto) by any means," the 23-year-old said after improving to 9-0 with seven KOs.
Ginjiro failed to win a championship outright in his first world title bout on Jan. 6, but that fight was declared a no-contest due to an accidental head butt suffered by Mexican champion Daniel Valladares.
Yudai, the WBC's third-ranked contender, celebrated his 26th birthday by dispatching the seventh-ranked Mendez after knocking down the Puerto Rican in the fifth and seventh rounds.
Yudai was originally scheduled to face Panya Pradabsri for the world title before the Thai champion pulled out of the bout earlier this month due to illness.
"Us brothers have kept fighting since we were small, aiming to be world champions. But this (being interim champion) is not the goal," said Yudai, who also remained undefeated as a pro with seven wins, five by knockouts, without a draw.
"It's a start, rather. We need to get stronger. I'll give my best again next time."
