South Korean professional Mi Hyang Lee shot the round of her life to upset Lydia Ko and claim her first professional win at the ISPS Handa NZ Women’s Open hosted by Christchurch.

Mi Hyang Lee, the 20-year-old LPGA Tour player, who began the final round eight shots back from the lead, carded a course record nine-under par 63 to hold off World No.4 and defending champion Ko by one stroke.

The final group Ko (70) and Americans Beth Allen (70) and Anya Alvarez (73) all had the chance to force a playoff on the 54th hole but Allen and Alvarez missed the green and Ko missed her birdie chance from 25 feet.

Meanwhile Lee was on the practice putting green, preparing for sudden death, and was informed by her Dad that she was the New Zealand Open Champion.

“I came around to the clubhouse and my Dad said ‘You won’ because Lydia missed a birdie putt and I cannot believe,” said Lee.

She was surrounded by her old Korean amateur team-mates who poured water over her head and then moments later Ko gave her a hug to congratulate her on her come-from-behind win that earned her 30,000 Euros (NZD$50,000).

The bubbly professional said she never believed that she had a chance to win when she began the final round. Her 63 – which included seven birdies and an eagle – broke the course record of compatriot Seon Woo Bae who shot 64 in the second round of the championship last year.

“It’s my best score in my life and I made the course record too so I am so happy now,” said the World No. 256.

ISPS Handa NZ Women’s Open hosted by Christchurch: Final Scores

Clearwater GC, Christchurch (Par 72):

207 - Mi Hyang Lee (KOR)  72 72 63

208 - Lydia Ko (NZL)  69 69 70

209 - Anya Alvarez (USA)  70 66 73, Seonwoo Bae (KOR)  68 71 70, Beth Allen (USA)  71 68 70

211 - Bree Arthur (AUS)  75 70 66, Marion Ricordeau (FRA)  74 69 68, Sarah-Jane Smith (AUS)  69 77 65

212 - Nikki Campbell (AUS)  72 72 68, Hyun Soo Kim (KOR)  74 66 72

213 - Jessica Speechley (AUS)  70 70 73, Stacy Lee Bregman (RSA)  71 75 67, Kyu-Jung Baek (KOR)  70 69 74, Marta Silva Zamora (ESP)  72 70 71, Jing Yan (CHN)  73 69 71, Lorie Kane (CAN)  74 72 67, Charley Hull (ENG)  69 73 71

214 - Shelly Shin (AUS)  76 68 70, Breanna Elliott (AUS)  75 70 69

215 - Felicity Johnson (ENG)  74 70 71, Christel Boeljon (NED)  72 72 71, Vikki Laing (SCO)  71 72 72, Yu Yang Zhang (CHN)  77 69 69, Linda Wessberg (SWE)  73 71 71, Cecilia Cho (KOR)  73 72 70

216 - Ae Young Shin (KOR)  70 72 74, Lindsey Wright (AUS)  73 70 73, Jean Chua (MYS)  71 73 72, Caroline Bon (NZL)  71 75 70, Kristie Smith (AUS)  70 72 74, Cathryn Bristow (NZL)  72 71 73, So Young2 Kim (KOR)  73 72 71

217 - Mireia Prat (ESP)  73 71 73, Trish Johnson (ENG)  74 70 73, Caroline Afonso (FRA)  71 71 75, Hyeji Lee (KOR)  69 75 73, Eleanor Givens (ENG)  73 69 75, Viva Schlasberg (SWE)  72 74 71, Laura Davies (ENG)  72 74 71

218 - Melissa Reid (ENG)  72 74 72, Hannah Burke (ENG)  73 72 73, Noora Tamminen (FIN)  74 71 73, Caroline Martens (NOR)  71 73 74, Alison Whitaker (AUS)  75 71 72, Danielle Montgomery (ENG)  72 74 72, Nikki Garrett (AUS)  72 73 73, Stacey Keating (AUS)  71 72 75, Sally Watson (SCO)  72 70 76

219 - Keiko Kubo (JPN)  73 73 73, Xi Yu Lin (CHN)  74 72 73

220 - Stephanie Na (AUS)  72 73 75, Pamela Pretswell (SCO)  78 68 74

221 - Alexandra Vilatte (FRA)  69 74 78

222 - Corie Hou (AUS)  73 73 76