Golf: Ko easily through to second round

World golf No 1 amateur Lydia Ko progressed in style to the second round of the US girls' junior championship by beating American Mikayla Harmon 7 and 6. Photo / Getty Images.

World golf No 1 amateur Lydia Ko progressed in style to the second round of the US girls' junior championship by beating American Mikayla Harmon 7 and 6.

Ko, who qualified as the No 2 seed for the event at the Lake Merced Golf Club in California, set up a second round match with Californian Hee Wook Choi.

Ko lost the first hole with a bogey, but it was all one way traffic after that as she won eight holes in an 11 hole stretch.

"I had a great drive, and I nearly shanked [my approach shot] and it went way right," said Ko. "'I was like, 'what is today going to bring me?"'

In the end, the day brought victory as Ko immediately won the second hole to square the match and never again trailed.

"I don't think there were much negatives in my round today," she said. "It's good to see my scores improving day by day."

Ko will square off with Choi in round two after the No 31 seed overcame the No 34 seed and fellow Californian Cha Cha Willhoite by 4 and 3.

Meanwhile, No 1 seed Ariya Jutanugarn continued her mastery, cruising to a 6 and 5 victory over Ji Eun Baik.

The defending champion and world No 2 amateur threw six birdies at Baik en route to shooting the equivalent of six under par.