After the first quarter ended, the SeaHorses Mikawa held the slimmest of margins on Friday night in Kariya, Aichi Prefecture.
Then the SeaHorses heated up on offense and seized control of their game against the Rizing Zephyr Fukuoka.
The hosts dominated the second and third quarters, built a large cushion and earned a 99-74 victory.
Mikawa, which led 17-16 entering the second quarter, outscored Fukuoka 54-36 in the middle two periods and took a 71-52 advantage into the final stanza.
Kosuke Kanamaru paced the SeaHorses (10-10) with 23 points, including 5 of 9 from 3-point range. Four teammates also scored in double figures: Kennedy Meeks (17 points), J.R. Sakuragi (14), Grant Jerrett (13) and Takanobu Nishikawa (10).
Meeks, a former University of North Carolina player, added 15 rebounds and seven assists, while Sakuragi had eight boards and seven assists.
The SeaHorses shot 55.6 percent from the floor; the Rizing Zephyr converted 36.4 percent of their attempts.
Dexter Pittman led Fukuoka (4-16) with 21 points. Masashi Joho and Yasuhiro Yamashita had 12 and nine points, respectively.
Second-division update
In Friday's B2 game, the Earthfriends Tokyo Z defeated the visiting Hachioji Bee Trains 88-75.
Tokyo improved to 9-11. Hachioji fell to 3-17.
The Bee Trains' Yu Okada, who scored 19 points, topped the 7,000-point career milestone.
Earthfriends big man Mogga Lado had 25 points and teammate Nigel Spikes scored 19 and grabbed 17 rebounds.
Former New York Knicks forward Cleanthony Early paced Hachioji with 30 points and 13 rebounds in his B. League debut. Early was 1 of 10 from 3-point range. He made 9 of 12 foul shots.