New Zealand teenager Lydia Ko has ended a huge rookie pro season in triumph, collecting the largest payoff in women’s golf.

Ko, 17, claimed the $US1 million ($A1.08 million) bonus for clinching the season-long points race on Sunday and then won a three-way playoff for the Tour Championship title at the fourth extra hole, collecting another $US500,000 ($A541,000).

The triumph doubled the career earnings for the world No.3, who made her debut as a professional at the Florida event 12 months ago,

It was her third victory on the LPGA Tour in a first season that included 15 top-10 placings in 26 events.

Ko said that her focus had remained on her game rather than the money going into a tense final day.

“I really didn’t think about it – even playing today when I was out there I just set myself a goal, to make myself as many birdies, and go out there and have fun,” she said.

“This has been a big year, a rollercoaster ride, and I’ve learned so much.

“These kinds of playoffs, it’s my first time as a professional and I’ve been learning lots.”

Ko went into the final round three shots off the pace in a share of fifth, but finished with a four-under 68 to draw even with overnight leader Julieta Granada of Paraguay and Spain’s Carlota Ciganda after 72 holes.

Granada dropped out of the playoff after bogeying the par four 18th at the second time of asking, leaving Cigata and Ko to battle it out head to head.

Cigata missed a five-foot putt for the win on the third time round as Ko again parred, then hit her approach off the green into the lakeside tussock on the fourth sudden-death hole.

The Spaniard took the drop, then missed her chip in for par, while Ko parred again to wrap up the biggest win of her career.

Ko was last week named LPGA Rookie of the Year.