Serbia's Jelena Jankovic crushed leg-weary Caroline Wozniacki to reach the semi-finals of the WTA Championships while American holder Venus Williams reached the last four on Friday without hitting a ball.
Holder Venus Williams launched her bid for a sixth Wimbledon title with a competitive 6-3, 6-2 victory over Swiss teenager Stefanie Voegele on Tuesday.
Holder Venus Williams completed her circuitous route to the WTA Championships final, beating Serbia's Jelena Jankovic 5-7, 6-3, 6-4 on Saturday to set up yet another showdown with sister Serena. Serena, who will end the year as world number one for the first time since 2002, got past Caroline Wozniacki after the Dane pulled out with a stomach injury when trailing 6-4, 0-1.