(Adds quotes) * Inkster one shot off the pace * Ko looking refreshed after time off April 23 (Reuters) - Lydia Ko fired an opening round five-under-par 67 on Thursday to take a one-stroke lead at the Swinging Skirts LPGA Classic, where she recorded her first win as a professional last year. World number one Ko, on the eve of her 18th birthday, made six birdies with just one bogey at the Lake Merced Golf Course in San Francisco. "Holed some good putts and ended up with a 67 today," Ko told reporters. Hopefully I can continue hitting solid shots." Ko has already won twice this year but took some time off after finishing well out of the picture at the ANA Inspiration, the women's first major of the season. More...