Mertens retires from match in Istanbul due to leg injury

ISTANBUL (AP) — Top-seeded Elise Mertens retired from her opening match at the clay-court Istanbul Championship on Wednesday because of a leg injury.

The 26-year-old Belgian was losing 7-5, 4-1 to Sweden's Rebecca Peterson when she retired with pain in her right leg. Mertens was runner-up to Sorana Cirstea last year.

Croatian player Petra Martic upset fourth-seeded Anhelina Kalinina of Ukraine 3-6, 7-5, 7-6 (5).

Later, Cirstea faces Dutch player Arantxa Rus in the second round. The 32-year-old Romanian last year ended a 13-year wait for her second career singles title when she upset Mertens in the final.

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