Czech Republic's Karolina Pliskova has withdrawn from this week's Prague Open and will be replaced by Aliaksandra Sasnovich in the main draw.
The world number six was the top seed in Prague and was scheduled to face twin sister Kristyna Pliskova in the first round of their home tournament on Tuesday.
"Karolina Pliskova has withdrawn from Prague... Aliaksandra Sasnovich moves into Pliskova's spot and will play Kristyna Pliskova," the Women's Tennis Association (WTA) said on Twitter on Monday.
Former world number one Pliskova beat American CoCo Vandeweghe to win her first title of the year at the Porsche Tennis Grand Prix on Sunday.
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