With just a few minutes to go in the two-hour afternoon session, Yamamoto set a time of 1m22.464s in his Honda-powered SF23, beating Tomoki Nojiri’s morning benchmark by 0.046s.
It meant the three-time Super Formula champion ended both Fuji test days on top, although his time on Saturday afternoon was significantly slower than the 1m21.897s lap he managed in cooler conditions on Friday.
Yamamoto was among a handful of drivers who set their best times late in the second session, as most drivers got their qualifying simulations out of their way in the morning when OTS wasn’t available.
For instance, Nojiri recorded his time of 1m22.510s just an hour into the morning session, just after the track went back to green after a brief red flag caused by Kondo Racing driver Kazuto Kotaka stopping on track with a technical issue.
The Mugen driver wouldn't go for another quick lap in the afternoon and ended up down in 21st in that session's individual leaderboard.
Yamamoto’s Nakajima team-mate Ren Sato set a lap that would be good enough for third right at the end of the morning session, as he ended up just 0.016s behind Nojiri with a time of 1m22.526s.
Dandelion Racing’s Tadasuke Makino finished 0.035s behind Sato in fourth, just days scoring his first podium of the season at Sugo.
Kamui Kobayashi enjoyed a strong day of testing in fifth for KCMG, while Red Bull junior and Mugen driver Liam Lawson was sixth with a time of 1m22.676s.
Both Inging’s Sho Tsuboi and Impul driver Ryo Hirakawa set their quickest laps in the afternoon session and ended up seventh and eighth respectively in the overall order, separated by just 0.009s.
TGM’s Toshiki Oyu was classified ninth after retiring from last weekend’s Sugo race with floor damage, while championship leader Ritomo Miyata was 10th-fastest, 0.436s off the pace.
Miyata’s new team-mate Ukyo Sasahara, who replaces Giuliano Alesi at TOM’S for the remainder of the season, was 18th and 15th across the two sessions.
Hiroki Otsu spent the entire day testing the B-Max car belonging to Nobuharu Matsushita and clocked a best time of 1m23.082s during the afternoon running.
Apart from Kotaka’s stoppage, the second day of Fuji test featured no major interruptions, although KCMG driver Yuji Kunimoto did suffer a half spin at the start of the second session.
Afternoon results:
| Position | Driver | Team | Lap Time |
|---|---|---|---|
| 1 | Naoki Yamamoto | TCS NAKAJIMA RACING | 1'22''464 |
| 2 | Tadasuke Makino | DOCOMO TEAM DANDELION RACING | 1'22''707 |
| 3 | Kamui Kobayashi | Kids com Team KCMG | 1'22''714 |
| 4 | Sho Tsuboi | P.MU/CERUMO・INGING | 1'22''764 |
| 5 | Ryo Hirakawa | ITOCHU ENEX TEAM IMPUL | 1'22''773 |
| 6 | Liam Lawson | TEAM MUGEN | 1'22''831 |
| 7 | Ren Sato | TCS NAKAJIMA RACING | 1'22''852 |
| 8 | Ritomo Miyata | VANTELIN TEAM TOM'S | 1'23''056 |
| 9 | Kakunoshin Ota | DOCOMO TEAM DANDELION RACING | 1'23''069 |
| 10 | Hiroki Otsu | B-Max Racing Team | 1'23''082 |
| 11 | Sena Sakaguchi | P.MU/CERUMO・INGING | 1'23''087 |
| 12 | Kenta Yamashita | KONDO RACING | 1'23''186 |
| 13 | Kazuya Oshima | docomo business ROOKIE | 1'23''230 |
| 14 | Toshiki Oyu | TGM Grand Prix | 1'23''292 |
| 15 | Ukyo Sasahara | VANTELIN TEAM TOM'S | 1'23''339 |
| 16 | Yuji Kunimoto | Kids com Team KCMG | 1'23''342 |
| 17 | Nirei Fukuzumi | ThreeBond Racing | 1'23''536 |
| 18 | Kazuto Kotaka | KONDO RACING | 1'23''544 |
| 19 | Raoul Hyman | B-Max Racing Team | 1'23''873 |
| 20 | Yuhi Sekiguchi | ITOCHU ENEX TEAM IMPUL | 1'24''037 |
| 21 | Tomoki Nojiri | TEAM MUGEN | 1'24''318 |
| 22 | Cem Bolukbasi | TGM Grand Prix | 1'24''814 |
Morning results:
| Position | Driver | Team | Lap Time |
|---|---|---|---|
| 1 | Tomoki Nojiri | TEAM MUGEN | 1'22''510 |
| 2 | Ren Sato | TCS NAKAJIMA RACING | 1'22''526 |
| 3 | Tadasuke Makino | DOCOMO TEAM DANDELION RACING | 1'22''561 |
| 4 | Kamui Kobayashi | Kids com Team KCMG | 1'22''617 |
| 5 | Naoki Yamamoto | TCS NAKAJIMA RACING | 1'22''666 |
| 6 | Liam Lawson | TEAM MUGEN | 1'22''676 |
| 7 | Toshiki Oyu | TGM Grand Prix | 1'22''883 |
| 8 | Sho Tsuboi | P.MU/CERUMO・INGING | 1'22''888 |
| 9 | Ritomo Miyata | VANTELIN TEAM TOM'S | 1'22''900 |
| 10 | Kakunoshin Ohta | DOCOMO TEAM DANDELION RACING | 1'23''127 |
| 11 | Kenta Yamashita | KONDO RACING | 1'23''132 |
| 12 | Hiroki Otsu | B-Max Racing Team | 1'23''137 |
| 13 | Nirei Fukuzumi | ThreeBond Racing | 1'23''258 |
| 14 | Sena Sakaguchi | P.MU/CERUMO・INGING | 1'23''275 |
| 15 | Ryo Hirakawa | ITOCHU ENEX TEAM IMPUL | 1'23''319 |
| 16 | Yuji Kunimoto | Kids com Team KCMG | 1'23''377 |
| 17 | Kazuya Oshima | docomo business ROOKIE | 1'23''555 |
| 18 | Ukyo Sasahara | VANTELIN TEAM TOM'S | 1'23''570 |
| 19 | Kazuto Kotaka | KONDO RACING | 1'23''610 |
| 20 | Yuhi Sekiguchi | ITOCHU ENEX TEAM IMPUL | 1'23''714 |
| 21 | Cem Bolukbasi | TGM Grand Prix | 1'23''734 |
| 22 | Raoul Hyman | B-Max Racing Team | 1'24''135 |
