Lydia Ko was horrified to learn Richie McCaw had watched her first six holes at the Rio Olympics - just when she was at her worst.

Ko is an unabashed fan of the retired All Blacks captain so was startled to hear he was in the gallery for the opening third of her round.

"Really, I didn't know. I would have probably taken a photo," the world's No.1-ranked woman said.

Ko, 19, was disappointed by her loose start to tournament, making two early bogeys before a birdie on the sixth, the last hole McCaw watched but ended the day two-under, four shots off the pace.

Advertisement

She hoped the Test rugby great won't be put off returning to the Marapendi course again this week.

"It's pretty cool he came out to watch. I didn't make a lot of birdies during that front nine.

"Maybe he saw at least one of them." Ko says every time she contests the New Zealand Open in Christchurch, she tries to catch up with good friend and All Blacks fullback Israel Dagg.

"I've gotten to know Israel pretty well. "I'd always said, when I play the New Zealand Open, 'hey is Richie McCaw going to come out and watch. I'd love to meet him'."