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# Shirasaki and Hirobon Complete Okayama Sweep as F4 Japan's Front-Runners Tighten Their Grip
- URL: https://www.thehairpin.co/shirasaki-and-hirobon-complete-okayama-sweep-as-f4-japan-s-front-runners-tighten-their-grip/
- Published: 2026-06-17T00:00:00.000Z
- Updated: 2026-06-17T00:00:00.000Z
- Description: Rounds 3 and 4 of the 2026 F4 Japan Championship at Okayama International Circuit produced a rare display of dominance across both classes, with Ryo Shirasaki and Hirobon sweeping pole positions and race victories to strengthen their positions at the top of their respective campaigns.
- Author: Sasha Mathews
- Tags: This Week in Motorsport

In the Champion Class, Shirasaki controlled the weekend from start to finish. The Japanese driver secured pole position for both races and converted each opportunity into victory, leading home Masana Muto in identical one-two finishes across the two rounds. Muto matched Shirasaki's consistency throughout the weekend, qualifying and finishing second in both races to maintain pressure in the championship standings.

The battle for the final podium position provided the main variation between the two races. Round 3 saw Ryutaro Sakai qualify third, but it was Ryo Sakai who claimed the final podium position in the race. By Round 4, Ryutaro Sakai returned to form, qualifying third and converting it into a third-place finish to complete the podium.

The Independent Class followed a remarkably similar script. Hirobon proved untouchable throughout the weekend, taking pole position and victory in both rounds. Kentaro established himself as the clear second-best performer, qualifying and finishing second in both races.

Behind them, the fight for third shifted between rounds. Masayuki Ueda started third in qualifying on both occasions, but Ikari claimed the final podium spot in Round 3 before Ueda reclaimed third place in Round 4.

As the championship moved into its second half, the Okayama weekend reinforced the hierarchy emerging in both classes. Shirasaki and Hirobon leave the circuit having established themselves as the benchmarks, while their closest rivals search for answers before the next round.