Eighth-seed Caroline Wozniacki overcame a one-set deficit to outmaneuver Sabine Lisicki of Germany 2-6, 6-3, 6-3 and move into the second round of the Dubai Championships.
Wozniacki, who won this tournament in 2011, will face German qualifier Annika Beck in the second round.
"I knew she was going to come out hot and just go for her shots, and I felt like I was just a step behind,'' said Wozniacki. "It was nice to win this one.''
Beck defeated Samantha Stosur of Australia 1-6, 6-1, 6-4. Fifth-seeded Jelena Jankovic of Serbia beat qualifier Maryna Zanevska of the Ukraine 6-4, 6-3.
Seventh-seeded Simona Halep of Romania retired with a right Achilles injury and fatigue while trailing Alize Cornet of France 6-1, 1-1. The ninth-ranked Halep, who won the Qatar Open on Sunday, complained of an inflamed Achilles during her run to the Doha title.
"I wanted to try because I like to try to fight for my chance, but here I couldn't," Halep said. "After one set I realised that it is dangerous to continue."