Hannah Green aims to harness extra confidence from becoming a two-time LPGA Tour winner after claiming the Portland Classic title in a thrilling final-group shootout. Already a major champion, 22-year-old went into the final round at Columbia Edgewater Country Club three shots behind American teenager Yealimi Noh and shot a five-under 67 to beat the precocious Monday qualifier by one stroke with a 21-under total.

Green drew level with Noh when she holed a lengthy, curling putt at the 17th hole and closed it out with a two-metre par putt at the last as her playing partner made bogey. The West Australian had to overcome a big stumble in the third round when she shot 73 to squander the five-shot lead she had built after opening rounds of 64 and 63. She did so while battling head-to-head with 18-year-old Noh in the final group, making six birdies – three on each nine – as she turned up the heat on the rookie, who shot 71.

Green said lessons from her maiden victory at the Women’s PGA Championship in June had paid off. “I can definitely say having that experience helped me, especially over the last five holes,” she said. “Grinding out and making sure that I stayed patient. I think the putt on 17 was obviously huge to get me tied with Yealimi coming into the last hole. And the clutch putt on the last is something that I will remember for a long time.”

In her second year on the tour, Green went into the tournament as world No 26 and is set to climb to a career high ranking when they updated on Monday. Her $US195,000 winner’s cheque took her season earnings to $US979,519 for the season and her career earnings to $US1,223,993.

“I definitely don’t want to get too ahead of myself,” Green said. “The win at KPMG I was really surprised with and even the first two rounds this week I was surprised with. So I don’t want to get too cocky but I also want to make sure that I don’t sell myself short and hopefully get myself in this position more.”

Noh finished three shots clear of third-placed Brittany Altomare but was shattered after missing out on becoming only the third Monday qualifier to win on the tour. “It’s hard,” an emotional Noh said. “I tried my best. My shots weren’t going how I wanted today.”