It was the first competitive match for Halep since she won the Dubai Championships in February for her 20th career WTA title. Before the Wimbledon champion recovered from a foot injury she sustained in Dubai, the coronavirus pandemic forced a five-month break.
The Romanian dropped her serve six times and double-faulted eight times before prevailing in a tiebreaker on her seventh match point.
“After the second set, I felt tired,” Halep said. “But I knew she was in the same position so I just had to stick to the plan and fight. The fighting helped me to win the match.”
She will face next Czech wild-card entry Barbora Krejcikova.
Second-seeded Petra Martic, who reached the semifinals in Palermo last week, overcame Varvara Gracheva 7-6 (2), 6-3 and will face Kristyna Pliskova in the second round.
Third-seeded Elise Mertens recovered from a second-set scare to beat Jasmine Paolini 7-5, 4-6, 6-3.
However, four of the top-10 seeded players went out.
Fifth-seeded Ekaterina Alexandrova was upset by Lesia Tsurenko 6-2, 6-4, No. 6 Anastasia Pavlyuchenkova lost to Arantxa Rus 7-5, 6-2, Sara Sorribes Tormo eliminated seventh-seeded Barbora Strycova and Irina-Camelia Begu dispatched ninth-seeded Anastasia Sevastova 6-2, 6-2.
Camila Giorgi, Magdalena Frech, Ana Bogdan and Leonie Kung also advanced.
The Prague Open is the second European tournament in the WTA’s restart amid the coronavirus pandemic, with strict health protocols in place.
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