Taiga Semikawa maintained his position atop the leaderboard, navigating the challenging conditions at the Vantelin Tokai Classic with a second-round one-over-par 72.
The 22-year-old, who had led by two shots after opening with a record-breaking 61 yesterday, was unable to extend his advantage due to windy conditions at Miyoshi Country Club's West Course in Aichi.
After Semikawa managed only a single birdie in the opening 10 holes, his back nine proved more challenging, with bogeys on holes 11, 13, and 17.
However, a timely birdie on the 15th placed him one shot ahead of Yuta Kinoshita and Ryosuke Kinoshita (no relation), who carded rounds of 70 and 69, respectively.
Takumi Kanaya, chasing the title of JGTO prize money king, is just one shot behind following 68, while Rikuya Hoshino is certainly doing his sponsor and tournament host, Vantelin, proud when he delivered the day's lowest round of 66, moving him into contention and tying for fifth place on 136.
Despite experiencing a totally different circumstance, Semikawa remains in high spirits.
"Although my putts and shots weren't on point, I found myself practising a lot of patience on the course. I genuinely believe that if my putting had been consistent, the score might have improved by four or five strokes,” said Semikawa, who rose to prominence after winning both the Panasonic Open and the Japan Open as an amateur last year.
"On the 13th, my tee shot felt spot-on, but it unexpectedly landed in a bunker. From what looked like a favourable position, I erred. That, combined with my putting, are areas I'd look into.
"The pin positions will likely change tomorrow, but given how I persevered today, I'm optimistic.
"For tomorrow, instead of over-focusing on the wind, I want to hit the ball straighter, keeping my eyes firmly on it.
"If I can hold onto the positivity from day one and concentrate on each shot, I think I can navigate this challenging course. My goal? A few birdies, maybe three or four, and if the putts come through, perhaps even six."
American Shintaro Ban, South Korea's Yang Ji-ho and Philippines Juvic Pagunsan are the best-placed international players in tied 22nd at seven shots off the pace.
Yang, the Hana Bank Invitational winner in June, shot 71 while Golf Partner Pro-Am Tournament champion Pagunsan and Ban posted matching 69s.
Leading second round scores:
133: Taiga Semikawa 61-72;
134: Yuta Kinoshita 64-70, Ryosuke Kinoshita 65-69;
135: Takumi Kanaya 67-68;
136: Koshiro Maeda 67-69, Rikuya Hoshino 70-66, Yuki Inamori 67-69;
137: Takashi Ogiso 66-71, Kodai Ichihara 69-68, Kensei Hirata 69-68, Taisei Shimizu 63-74.