Andy Sullivan and Kim Yeongsu posted opening 63s to lead the way after the first round of the 2023 ISPS HANDA - CHAMPIONSHIP in Japan.
Four-time DP World Tour champion Sullivan fired eight birdies at PGM Ishioka Golf Club on Thursday, with his only blemish a bogey on the seventh.
South Korean Kim, the KPGA’s 2022 Genesis Point Award winner, produced a flawless first round containing seven birdies to join Sullivan on seven under par.
Swede Alexander Björk, Canada's Aaron Cockerill and South African Deon Germishuys were one shot behind the leaders in a three-way tie for third.
Home favourites Keita Nakajima, Yosuke Asaji and Ryutaro Nagano were then on five under alongside Jacques Kruyswijk, Sebastian Söderberg, Brad Kennedy, Daniel Hillier and Marcel Schneider.
Sullivan started from the tenth tee and made birdies at the 12th, 15th, 16th and 18th to reach the turn in 31.
He then reeled off a hat-trick of birdies from the third before recovering from a bogey on the seventh with a closing gain from around eight feet.
The Englishman said: "Really pleased, just got off to a good start.
"A lot of right flags out there for me to find - as my playing partner Romain Langasque told me! He was like 'Every flag out there is a right flag and you fade the ball so it’s perfect for you today'.
"It was good fun playing with Brendan (Lawlor) and Romain, very relaxed vibe. It was just like going out there and playing with your mates, really.
"Me and my coach have been working on going back to when I was playing my best, around 2015, 16, so we’ve looked at swings from there and almost tried to mimic that.
"It’s getting close, feel confident with the irons. Driver is still taking a bit of work. On the whole the game is feeling good. It feels a lot more under control again, less of the erratic shots."
Kim picked up his first birdie of the day at the fourth before catching fire around the turn, as he reeled off six birdies in eight holes from the ninth for a share of the lead.
He said: "I feel good because I didn’t make any bogeys today.
"My shots were not in good shape at the beginning. However, it seems I putted well, so that helped today’s score.
"I hope it goes well tomorrow. I will be able to play with less stress because I played well today."
