CARLSBAD, Calif. – Jin Young Ko picked up where she left off three weeks ago in Singapore on Thursday in the first round of the JTBC Classic.

The top-ranked Ko shot a bogey-free 7-under 65 at Aviara Golf Club to take a one-stroke leader over Nanna Koerstz Madsen in the final event before the first major of the season next week at Mission Hills.

“I love to play golf right now,” Ko said. “I’m really enjoying right now on the course, playing with whoever. I can focus myself. Shot by shot I can. Feel confidence 100% and I can focus 100% for my ball. I love to play golf right now.”

The victory in Singapore in the HSBC Women’s World Championship in her only other LPGA Tour start of the year was her sixth in her last 10 tournaments and 13th overall. On Thursday, the South Korean star extended her tour record for consecutive rounds in the 60s to 16 and sub-par rounds to 31.

“I’m just trying to hit 60s today,” Ko said. “These greens are really tricky, so I didn’t expect for good putt or make a lot of putts on this green. But I made a lot of birdie today and bogey-free round. It’s pretty so far, so looking for next three days.”

She’s preparing for The Chevron Championship, the major tournament she won in 2019 that is being played at Mission Hills for the final time.

“I love to play in West Coast, and especially before the major,” Ko said. “I need to warm up before the first major of the year.”

Koerstz Madsen won the Honda LPGA Thailand two weeks ago to become the first Danish winner in LPGA Tour history. She had a late eagle on the par-5 eighth in her afternoon round.

“I’m very pleased with the score,” Koerstz Madsen. “I think I only hit maybe four fairways, so I was struggling. ... But I made some good putts out there, which I maybe wasn’t expecting.”

Cheyenne Knight was at 67 with Gemma Dryburgh and Hye-Jin Choi.

Lydia Ko, the 2016 winner, was another stroke back with Mo Martin, Maude-Aimee Leblanc, Ryann O’Toole, Pajaree Anannarukarn. Lydia Ko won the Gainbridge LPGA at Boca Rio in January.

“In general, I feel like I played solid and pretty consistently,” Lydia Ko said. “Hopefully, I’ll be able to carry that to the next few days.”

Race to CME Globe leader Danielle Kang shot a 69. She won the season-opening Tournament of Champions in January

Defending champion Inbee Park opened with a 71. Lexi Thompson shot 73.

Nelly Korda, the No. 2 player in the world, is sidelined as she recovers after being diagnosed with a blood clot in her arm.