A revitalised Tomoyo Ikemura boosted his prospects of winning his first JGTO trophy of the season, securing a three-shot lead at the halfway point of the Casio World Open with an impressive eight-under-par 64 on Friday.
The 28-year-old Ikemura's flawless round brought his 36-hole total to 12-under, with joint first-round leader Tsubasa Ukita and Ryu Hyun-woo of South Korea trailing closely behind at nine-under.
Ukita persevered through a tumultuous day to secure a 72, while Ryu, a two-time JGTO winner but not since 2017, posted a 69.
Yang Ji-ho, the other co-leader, slid down the leaderboard after a hard-fought 73, tying for fourth with South Korean compatriot Song Young-han, who carded a 70 to sit at eight-under.
Ikemura, who started the day five shots off the pace, carded nine birdies against a bogey - his first of the week - at the Kochi Kuroshio Country Club to surge up 16 spots from where was after the first day.
Ikemura said he had made the most of the ideal scoring conditions after being among the early groups to tee off.
"I was wondering if luck was on my side today, given the early start time. Despite the wind picking up in the last five holes, I considered it fortunate to finish strong on the outward nine," said Ikemura.
"I could reach the greens even in the strong wind, secure pars, and capitalise on birdie opportunities when in favourable So, one might say luck was on my side.
"As it's the second day, I believe I was able to adopt a more relaxed approach without overwhelming myself."
Ikemura, whose last victory came last year at the ASO Iizuka Challenged Tournament, has struggled to impress this season with a tied-seventh at the ACN Championship being his only notable outing.
He also missed the cut 10 times, including the last two starts at the Mitsui Sumitomo Visa Taiheiyo Masters and Dunlop Phoenix Tournament.
"I was struggling with the driver, waning confidence, and could not execute proper swings. After that, my irons also deteriorated, and I was stuck in a negative cycle throughout the mid-season," said Ikemura.
"Although I have won multiple times in the past, including last year, I refrained from rushing and evaluated my situation. Realizing that playing golf without a resolution was futile, I sought the guidance of a coach.
"Since then, my overall feeling has improved, and I'm finally experiencing a sense of return to my golf game."
Ukita lamented the cold putter as the reason for his modest round today, after trading three birdies against as many bogeys - a far cry from the superb nine-birdie flawless round in the previous day.
" Although I could position myself well when hitting from the fairway, I couldn't sink a single putt today," said the 22-year-old Ukita.
"Compared to yesterday, my putting touch was lacking, resulting in numerous near misses. The coordination between reading the greens and executing the putts wasn't quite there.
"For the weekend, I need to keep my emotions in check to avoid getting frustrated. I need to play with a calm and composed mindset all the time."
Leading second round scores:
132: Tomoyo Ikemura 68-64;
135: Tsubasa Ukita 63-72, Ryu Hyun-woo (Kor) 66-69;
136: Yang Ji-ho (Kor) 63-73, Song Young-han (Kor);
137: Eric Sugimoto 68-69, Takahiro Hataji 67-70;
138: Daisuke Kataoka 67-71, Todd Baek (US) 66-72, Ren Yonezawa 68-70, Tomoyasu Sugiyama 66-72, Han Lee (US) 68-70, Taichi Nabetani 69-69, Taiga Semikawa 66-72, Kaito Onishi 68-70, Yusaku Hosono 71-67, Takumi Kanaya 66-72.