Briton Watson needed nearly 3 1/2 hours and three sets before prevailing over Galina Voskoboeva of Kazakhstan, 7-5, 5-7, 7-6 (7-4) at the U.S. National Indoor Tennis Championships.
South Africa's Scheepers fell to American Coco Vandeweghe 6-2, 6-1.
Lauren Davis of the United States beat Ksenia Pervak of Kazakhstan 5-7, 6-1, 6-3 in another first-round match.
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