American Serena Williams defeated Russia's Maria Sharapova 6-4, 6-3 in the final of the WTA Tour Championships on Sunday in Istanbul.

Williams, who also won the year-end tournament in 2001 and 2009, needed only one hour and 29 minutes to overpower the Russian.

The American, who will finish the year ranked No. 3, has saved her best game for the big events and dominated Sharapova in recent years.

Williams has now won 10 of the 12 matches she has played against the Russian and nine matches in a row.

The doubles title was won by the Russian team of Maria Kirilenko and Nadia Petrova, who defeated Czechs Andrea Hlavackova and Lucie Hradecka 6-1, 6-4. EFE