JERSEY CITY, N.J. (AP) — So Mi Lee shot a 6-under 66 after getting into the field less than two hours before her tee time and took a two-shot lead Thursday after the opening round of the Mizuho Americas Open got off to a surprising start with the withdrawal of defending champion Rose Zhang because of illness after three holes.

Withdrawals were one of the stories of the first round. Besides Zhang, who was coming off a win in the Cognizant Founders Cup last weekend, Maja Stark of Sweden and Caroline Masson of Germany also withdrew because of illness.

Lee, 25, of South Korea replaced Stark and Mao Saigo, 22, of Japan got Masson’s spot. They are right at the top of the leaderboard.

A five-time winner on the Korean LPGA tour, Lee had eight birdies and two bogeys in her round on the Liberty National course in the shadow of New York City. Saigo had five birdies and a bogey, in finishing tied for second with three other players with 68s.