PRAGUE — Magda Linette of Poland upset No. 3 seed Elise Mertens of Belgium 6-3, 2-6, 6-2 in the first round of the Prague Open in the Czech Republic.
Mertens struggled with her service game, posting seven double faults as Linette converted five of 13 break points.
Two other seeded players were in action Monday. No. 8 Marie Bouzkova of the Czech Republic eliminated Austria’s Sinja Kraus 6-2, 7-6 (2).
No. 6 Alison Van Uytvanck of Belgium was losing 5-2 in the first set when she was forced to retire from her match with Slovenia’s Dalila Jakupovic.
World No. 2 Anett Kontaveit of Estonia is the top seed for the WTA 250 hard-court event and will face Ekaterine Gorgodze in the first round.
Poland Open
Lucky loser Laura Pigossi of Brazil knocked out No. 9 seed Varvara Gracheva of Russia 6-2, 6-2 in the opening round in Warsaw.
Pigossi, who got into the draw when Palermo champion Irina-Camelia Begu withdrew, saved seven of nine break points and converted five of her seven break chances.
No. 5 Caroline Garcia of France, the only other seeded player in action, pulled out a 7-5, 6-4 win against Misaki Doi of Japan in just under two hours.
World No. 1 Iga Swiatek of Poland is the top seed on home soil for the WTA 250 clay-court tournament. She opens against compatriot Magdalena Frech on Wednesday.