DAVAO CITY — Sarah Ababa drained a lengthy birdie putt on No. 17 to spike a gutsy 72, pulling ahead by one over Mikha Fortuna and rookie Mafy Singson in an unpredictable start to the P1-million ICTSI Ladies Apo Golf Classic here Thursday.

Ababa's dramatic putt from 24 feet on the penultima hole of the Apo course, where she honed her skills, brought stability to a rollercoaster round where the leaderboard witnessed constant changes with every missed shot and converted putt.

"The course conditions are challenging. I didn't set a goal, just enjoying it because this is my home course," said Ababa, aiming to break a long nine-year title drought on the Ladies Philippine Golf Tour.

She credited her father-caddie for providing valuable support, saying: "My father was a big help. I played relaxed. In fact, after I bogeyed No. 1, he told me that it was a good start."

Ababa, who edged Chihiro Ikeda and Korean Hwang Min Jeong at Sherwood Hills in 2015 for her career breakthrough, birdied the par-5 No. 3, yielded another stroke on the next then broke a run of pars with that big putt on the 17th.

But hot on her trail are two former national team standouts as Fortuna endured a tough frontside test, finishing with a birdie on the last hole to salvage a 73. Singson, on the other hand, bogeyed the 18th for a 38-35 and missed joining Ababa at the top.

"The course is narrow and the greens are pretty hard. It was colorful but tough day," said Fortuna, eyeing a follow-up to her victory in the season-ending ICTSI Match Play Invitational last year.

"I had a challenging start, I only made two pars on the front nine," added Fortuna, who fumbled with five bogeys against two birdies in the first nine holes.

But she stayed patient throughout, picking up strokes on Nos. 10 and 13 and recovering from a mishap on the 17th with a closing birdie.

"With how I played, I think it was okay. I'm proud of myself, how I was able to stay composed," she said. "It was a tough battle throughout, it requires a different strategy and I hope for the best tomorrow."