ANTIPOLO CITY — Young Yunju An reinforced her remarkable first-round performance by posting a tournament-best two-under 69, shocking seasoned pros with a commanding five-shot lead in the second round of the Ladies ICTSI Forest Hills Classic here on Thursday.

Despite her limited experience on the daunting Forest Hills’ Nicklaus course, which she’s only played a couple of times, the 13-year-old prodigy displayed remarkable composure. She held her own with a par 35 on the front nine, then surged ahead of the field with back-to-back birdies from No. 16.

An’s stellar play increased her overnight two-stroke advantage to a commanding five-shot margin over fellow Korean Jiwon Lee, pooling an even 142 with 18 holes left to play.

Few expected the young sensation, who is participating in her first professional event, to dominate so convincingly over her seasoned rivals.

An’s recent victory in the Junior PGT at Mount Malarayat already demonstrated her immense potential, but her performance here is turning heads beyond mere promise.

She admitted through an interpreter, “My game? I don’t think it was bad.”

She recorded two birdies and two bogeys in the first six holes and parred the rest before closing out with her signature birdies.

Even after posting the day’s best score, An remained grounded.

“Today, I didn’t have a good shot, unlike in the first round where my shots and putting were good,” she said, pointing to the challenging weather.

“It’s raining in the middle of the round, and it was a little bit hard.”

With her sights set on the title, An aims to maintain her calm demeanor in the final round, focusing on improving her putting to secure her first pro victory in the circuit organized by Pilipinas Golf Tournaments Inc.

Lee, who impressed with a victory at Splendido Taal last July in her pro debut, finished with a frontside 34 to stay within reach of An. However, she faltered in the stretch, making three bogeys against a lone birdie to end up with a 72 for a 147, five strokes behind her compatriot.

Gretchen Villacencio closed with a 73 for third at 150, trailing by eight shots, while Velinda Castil carded a 72 to tie Chihiro Ikeda and Miya Legaspi, both at 151 after 75s.