KEY BISCAYNE (AP) — No. 4-seeded Andy Murray advanced in a walkover Sunday at the Sony Ericsson Open when Milos Raonic withdrew because of a sprained right ankle.

Raonic said he doesn’t believe the injury is serious. Murray, the 2009 champion, moved into the fourth round.

Grigor Dimitrov advanced by upsetting No. 7 Tomas Berdych 6-3, 2-6, 6-4. The 20-year-old Dimitrov improved to 1-9 against top 10 players.

No. 9 Janko Tipsarevic beat No. 18 Alexandr Dolgopolov 6-4, 5-7, 6-2.

In women’s third-round play, No. 7 Marion Bartoli eliminated Simona Halep 6-4, 7-6, (6). No. 16 Dominika Cibulkova beat Zheng Jie 6-2, 6-0.

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