San Francisco, CA (SportsNetwork.com) - World No. 1 Lydia Ko birdied the second playoff hole on Sunday to defeat Morgan Pressel and successfully defend her title at the Swinging Skirts LPGA Classic.

Ko, who earned her first victory as a professional at this event last season, shot a 2-under 70 to finish regulation play tied with Pressel at 8-under 280. The win is Ko's seventh on the LPGA Tour and fifth since the start of the 2014 season.

"This week I hit the ball really well. It definitely makes his course a lot easier. Last year I wasn't hitting the ball good," Ko said. "The fans were awesome this week and it's always great to come back to a tournament where you guys are feeling the love."

Pressel, who had birdie putts to win both in regulation and on the first playoff hole, shot an even-par 72. Pressel was seeking her third win on tour and her first since 2008.

Second- and third-round leader Brooke Henderson carded a 2-over 74 and she finished in sole possession of third place at minus-7 at Lake Merced Golf Club.

Min Seo Kwak (74) ended one shot further back at 6-under 282, while Shanshan Feng (72) finished alone in fifth at minus-5.

After playing from behind all day, Ko sank some clutch birdie putts down the stretch to force the playoff. One shot back of Pressel heading to the 72nd hole, Ko poured in a birdie from about 12 feet to join her atop the leaderboard.

Pressel, playing in the last group just behind Ko, stuck her approach to about 20 feet but was unable to convert for the win.

Back on the par-5 18th for the first playoff hole, Ko missed her long birdie putt for the win, giving Pressel a shot from 10 feet. She came up just short and the duo went back to the 18th tee one more time.

Pressel watched as Ko hit her third to five feet and then put hers about 10 feet away. Again Pressel missed her putt, this time to the left on the low side, and Ko knocked her attempt in for the victory.

Ko got off to a rough start in her round as she tripped to back-to-back bogeys on one and two. The world's top player went on to birdie three and six to get back to even-par for the day.

"You know I started off pretty bad. Bogey-bogey, that really wasn't the way that I had planned it," Ko admitted. "But last year too I didn't play that front nine very well and then just made a couple birdies."

She then found herself four shots back as Pressel drained a long eagle putt from about 50 feet away at the par-5 sixth, getting her to minus-10. Pressel then went on to trade a bogey on seven for a birdie on eight.

In the meantime, Ko birdied No. 8 to stay within striking distance at 7-under. After a trio of pars from nine, Ko bogeyed 12 and fell four back again. A birdie on 13 got her back on track.

Pressel also went on to bogey 12, leaving Ko just two back. Ko rolled in a long, bending birdie on 15 and Pressel came back with a birdie of her own at 14.

"I just tried to make some birdies and you know that long putt on 15 definitely helped," Ko said.

While Pressel bogeyed her next two holes at 15 and 16, Ko also dropped a shot at 16, leaving her one back. She then went on to hole her birdie effort at 18, which eventually forced the playoff.

Henderson was up-and-down all day as she bogeyed two of her first three. A birdie on six got one of those shots back, but she later made back-to-back bogeys on 12 and 13.

A hole-out from the bunker for eagle on 14 had Henderson believing and just two back, but a bogey on 15 doomed her as she only managed to par the last three.

NOTES: Ko is now 2-0 in her career in playoffs, while Pressel drops to 0-2 ... Ko turned 18 years old on Friday ... Ko also repeated as champion at the 2013 Canadian Open when she was an amateur ... Pressel's last win came at the 2008 Kapalua LPGA Classic. She also won a major title at the 2007 Kraft Nabisco Championship ... This was the third straight playoff on the LPGA Tour and the fourth in 10 events in 2015 ... Ko earned $300,000 with this victory ... The LPGA heads to Texas next week for the Volunteers of America North Texas Shootout, where Stacy Lewis went on to win by six shots last year.