Kaia Kanepi has pulled out of WTA250 Tennis in the Land tournament in Cleveland, Ohio.
The world number 31 was due to take part in Tennis in the Land, and the reason for her withdrawal has not been reported. She is due to compete at the U.S. Open, which starts August 29.
Kanepi reached round two of the Canadian Open earlier this month, and went out in round one in this week's Western and Southern Open in Cincinnati.
All these competitions are effectively warmers for the U.S. Open, the last Grand Slam competition of the year.
Last year's winner of the Cleveland tournament, Estonia's Anett Kontaveit, currently second in the world, is also not taking part this year.
Kontaveit's spectacular end-of-year run, which culminated in her breaking the WTA top 10, the first time an Estonian had done so, began at Cleveland and included tournament wins in Russia and Romania, as well as an appearance at the season close in Mexico.
Editor: Andrew Whyte