Defending champion Maja Stark started the US Open shakily but ended the first round at par after six birdies.
After seven holes the 26-year-old Swede stood at four over par following two consecutive double bogeys and a bogey. She then improved and closed the round at par. Stark claimed her first major title last year at Erin Hills in Wisconsin. The event is held at Riviera Country Club in California. Among the seven Swedish players Madelene Sagström posted 77 while amateur Meja Örtengren carded 73.