Austin Ernst started strong and held on through two late bogeys Sunday, firing a final-round 70 to beat Jennifer Kupcho by five strokes in the LPGA Drive On Championship in Ocala, Florida.

Ernst started the day with a one-stroke lead over Kupcho, and built it to six with a burst of four straight birdies from fourth through the seventh holes.

Back-to-back bogeys at 12 and 13 saw her lead dwindle to three strokes, but Kupcho's challenge finally faded with a double-bogey at the par-three 15th and Ernst cruised home for her third LPGA Tour title with a 15-under par total of 273.

"The difference this week, I just fully committed to believing in what I do and that it's good enough," said Ernst, whose second title last August at the NW Arkansas Championship came six years after her first.

"I think this week it proved it was more than good enough," added Ernst, who held at least a share of the lead after every round.

Last-group playing partner Kupcho carded a two-over 74 for 278, the former top-ranked amateur remaining in search of her first LPGA win.

She couldn't match Ernst's strong start, dropping a shot with a bogey at the third before her first birdie of the day at the 10th cut Ernst's lead to five.

Kupcho applied more pressure at the par-five 12th, where her eagle attempt barely missed and left her a tap-in for birdie.

Ernst, meanwhile, was unable to get up and down and her bogey saw her lead shrink to three as they headed to 13.

"(At) 13, I just told myself I hit a good putt on 12 and I was still three-under for the day and still had the lead, and I was still playing good," Ernst said. "I just made one bad swing on 12."

After both bogeyed 13 and parred 14, Kupcho came unstuck at the 15th, where her tee shot found the water. Her third shot from the drop zone left her a lengthy bogey attempt and she walked off five adrift again.

Kupcho fell further back with a bogey at 17, but she birdied 18 for a two-stroke cushion over third-placed Jenny Coleman, who carded a 71 for 280.

South Korea's Chun In-gee posted a 69 for solo fourth on 281, and Switzerland's Albane Valenzuela was fifth after a 73 for 282.