Na's group was "on the clock" for most of the back nine, which in itself is nerve-racking and distracting for the players and can lead to further fines if a player gets put on the clock 10 times in a season.

WSJ: John Paul Newport on Slow Play | Golf Journal

World number two Na Yeon Choi of South Korea was in a five-strong group on five-under.

CNN: Tseng has company in battle for first women's major