KEY POINTS:
Venus Williams defeated her sister Serena 5-7, 6-1, 6-0 yesterday to reach the semifinals of the WTA Tour's season-ending Sony Ericsson Championships. Serena started to unravel early in the second set, and said the round-robin match was her worst of the year. Venus Williams won on her fifth match point to finish round-robin play with a 3-0. Serena Williams dropped to 1-1 but can still advance to the semis if she beats Elena Dementieva. The sisters are now 9-9 in heads-up play.