SAN FRANCISCO — Defending champion Lydia Ko shot a five-under 67 to seize the early lead at the LPGA Tour's Swinging Skirts Classic tournament Thursday. The world No. 1 from New Zealand looked confident and comfortable in the first round much like she did last year when she picked up her first professional win at this event. “I read most of (the greens) really well,” Ko said. “I tried to be confident with the reads I had. It's tough here so you can't really be overly aggressive.” Ko, who turns 18 Friday, has won six times on the LPGA Tour. Her first win came at the 2012 Canadian Open as an amateur. Juli Inkster, 54, posted a four-under 68 and she is tied for second, one stroke behind Ko at Lake Merced Golf Club. The 2015 Solheim Cup captain is joined there by Jang Ha-Na of South Korea and Thailand's P.K. Kongkraphan. Inkster hasn't won an LPGA Tour event since capturing her 31st career victory in 2006. “Age matters in a lot of things, as far as how your body feels, how far you hit the ball and how much time you can put into it — but you can still go out there and compete at 54,” Inkster said. World No. 2 Stacy Lewis headlines a group of four players tied for fifth at three under. Lewis finished the first round alongside Morgan Pressel, Caroline Hedwall and Choi Na-Yeon. Weekley, de Jonge set pace In New Orleans, American Boo Weekley, seeking his first PGA Tour victory in two years, took advantage of rain-softened conditions to grab a share of the lead in the Zurich Classic of New Orleans opening round Thursday. With a few family members spurring him on, the 41-year-old birdied four of his last eight holes to card an eight-under-par 64 at the TPC Louisiana, setting the early pace before being caught late in the day by burly Zimbabwean Brendon de Jonge. Canada's David Hearn and American Sean O'Hair fired 65s to finish a stroke in front of Englishmen Brian Davis and Greg Owen and Americans Daniel Berger, Mark Hubbard and Erik Compton while Australian Jason Day was among a group bunched on 67. Play was suspended for just over an hour during the afternoon because of heavy rain and 12 players will have to complete the opening round on Friday. Weekley, a three-times winner on the PGA Tour who lives in Florida, had an eagle, seven birdies and a lone bogey at a venue softened by more than nine inches of rainfall last week. Weekley also benefited from a new set of irons that worked well for him in Wednesday's pro-am competition. Australian world No. 6 Day relished playing in the company of seventh-ranked Dustin Johnson and his fellow American Ben Crane, who also carded 67s. “I made a great start, birdieing the first hole, and everyone kind of followed suit after that,” said Day. “The course is very receptive, it's very gettable. It was good to be a part of a group with DJ and Ben Crane. We had a lot of fun out there.” South Korea's Noh Seung-yul, who won last year's title by two shots, launched his title defence with a 73. — Agencies