Serena Williams won her third-successive WTA Finals title and fifth overall by beating Simona Halep 6-3, 6-0 on Sunday, avenging an embarrassing group-stage loss to the Romanian player. Halep easily beat Williams just four days earlier during the group stage of the tournament, but the American turned that around with an aggressive game plan. Williams won 11 of the last 12 games in the match to join Martina Navratilova and Steffi Graf as the only players to have won five titles in the season-ending championships. Serena Williams holds aloft the trophy after winning the WTA Finals in Singapore The world No 1 has equalled Steffi Graf and Martina Navratilova by winning the event five times
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Serena Williams defeated Simona Halep 6-3, 6-0 to win WTA Finals
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World No 1 has won the tournament five times, including  the last three
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Halep had beaten Williams in the group stages and could have denied her opponent a place in the final had she lost to Ana Ivanovic
Instead, Halep lost in three and @placeholder made it in.