Rex Tso improved his record to 20-0 (12 knockouts) with a 10-round unanimous-decision win over previously unbeaten Japanese boxer Ryuto Maekawa in front of a reported capacity crowd of 5,000 fans at Convention Towers and Exhibition Center in his native Hong Kong on Saturday.

Two judges saw the fight 98-92 for Tso while the third found just one round to give to Maekawa (11-1-1, 7 KOs) for a 99-91 tally.

Tso, nine years older than his opponent at 29, used his footwork in the first round to avoid the rushes from Maekawa while darting in with his own southpaw combinations. Tso, who had sparred for a month in the Philippines with WBO bantamweight titleholder Marlon Tapales for this fight, began to stand his ground more in Round 2, giving the visiting boxer the war he sought. Maekawa was able to land effectively with his right hands when Tso exchanged, and briefly stunned Tso at the beginning of Round 3 with a counter right as Tso leapt in with his own shot.

Tso remained an inviting target for the remainder of the round but closed the stanza with his own flurries, making a statement with a left uppercut-right hook which he followed up with body work.

By Round 4 Tso had accepted that the fight would be a brawl, firing a straight left hand, switching to an orthodox stance to fire a right cross, then switching back to southpaw to throw an overhand left and a sharp right hook to the body. Tso’s punches were more plentiful but Maekawa’s seemed heavier as he landed a left-right in return, followed by two rights which rocked Tso back. Tso’s commitment to the body and the fight’s torrid pace began to wear on Maekawa as Tso carried the rest of the fight with his superior workrate.

“He was very tough and it was 10 hard rounds. But I have taken another big step. It’s one more big step for me,” Tso told the South China Morning Post.

Tso, who has become a popular regional attraction through fights in Chinese territories Hong Kong and Macau, is rated in the top 15 by all 4 major sanctioning bodies at 115 pounds, and as high as No. 4 by the WBO. An official at Top Rank, which promotes Tso alongside DEF Promotions, said he had “no idea” what was next for Tso, while an email to Tso’s manager Jay Lau was not returned by the time of this story’s publication.

In other action, Australian junior featherweight Paul Fleming (23-0, 15 KOs) remained unbeaten with a second-round stoppage of Jerope Mercado (27-9-3, 9 KOs) in an eight-round scheduled bout. The fight was stopped at the 2:04 mark.