TOKYO (Kyodo) -- Rank-and-file grappler Atamifuji continued to be a thorn in the side of ozeki Hoshoryu on Thursday, handing the Mongolian star his first defeat of the New Year Grand Sumo Tournament.

The hulking 22-year-old executed an armlock throw to earn his maiden victory of the 15-day meet and take a 5-3 lead in his head-to-head history against Hoshoryu, who is aiming for promotion to yokozuna after going 13-2 as runner-up in November.

No. 2 maegashira Atamifuji (1-4) stood firm as Hoshoryu (4-1) attempted his trademark overarm throw, then clamped down on the ozeki's right arm and swung him to the clay at the edge of the ring.

"I was 0-4 so it feels good to win," Atamifuji said. "I felt my sumo was kind of sloppy today, to be honest, but I was able to eke out the win."

The result leaves No. 3 maegashira Oho in the lead at 5-0 alongside three fellow rank-and-file wrestlers -- No. 5 maegashira Chiyoshoma, No. 10 Tamawashi and No. 14 Kinbozan.

Oho pulled off the other big upset of Day 5 at Tokyo's Ryogoku Kokugikan arena when he earned his first career victory against ozeki Onosato (2-3) via rear push out, extending a win streak against opponents from the three "sanyaku" ranks below yokozuna.

"I just wanted to concentrate and not worry about my past record against Onosato," said Oho, the 24-year-old grandson of former yokozuna Taiho. "My opening charge has been solid as I've been able to put together this winning streak."

Ozeki Kotozakura, who also came in as a yokozuna promotion candidate following his breakthrough title in November, continued his forgettable start by dropping to 1-4 with a loss to No. 4 maegashira Shodai (2-3) by frontal crush out.

The action inside the ring on Day 5 was overshadowed by the injury withdrawal of lone yokozuna Terunofuji, who bowed out with a 2-3 record after forfeiting his scheduled bout against No. 3 maegashira Gonoyama (4-1).

The Mongolian-born grand champion hurt his right knee and lower back before the tournament, his Isegahama stablemaster said Thursday. His latest absence comes after he completed just two tournaments out of six in 2024, both of which resulted in him winning the Emperor's Cup.