Two-time Grand Slam winner Garbine Muguruza and 2018 finalist Daria Kasatkina survived tough opening day battles at the Dubai Duty Free Tennis Championships.
Twelfth-seeded Muguruza needed seven match points to overcome Ukraine's Dayana Yastremska 4-6, 6-3, 6-3, while Kasatkina took more than two hours to beat qualifier Magdalena Frech 6-3, 3-6, 6-4.
Canada's Eugenie Bouchard also booked her place in the next round with a straight-sets win over Vera Lapko 6-3, 6-4.
Meanwhile, former champion Sara Errani, tenth seed Anastasija Sevastova and Ekaterina Makarova were some of the big names who crashed out of the first round.
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