DOHA, Qatar (AP) -- The Williams sisters could be headed for a final matchup at the Sony Ericsson Championships after Venus Williams advanced to the semifinals along with Jelena Jankovic and Caroline Wozniacki on Friday.
Venus Williams, the defending champion, lost her first two group matches but advanced on sets thanks to Svetlana Kuznetsova's 6-3, 6-2 win over Elena Dementieva. Unbeaten Serena Williams had already gained the semifinals.
Venus Williams, Kuznetsova and Dementieva all finished with one win and two losses.
Jankovic advanced by routing a tired Wozniacki 6-2, 6-2, but the 19-year-old Dane also advanced when Victoria Azarenka had to retire against alternate Agnieszka Radwanska of Poland while trailing 4-6, 7-5, 4-1.
Azarenka would have advanced with a win, and served for the match twice in the second set. She then needed a medical timeout early in the third to treat her left thigh and lower back. She continued playing with the thigh taped, hobbling around the court and in obvious pain. She needed another timeout to treat leg cramps before the final game. She came back out, but called it quits while down 40-15.
Serena Williams will play Wozniacki in on semifinal on Saturday, and Venus Williams will face Jankovic at the same stage for the second straight year.
Both Williams sisters had the day off after playing on the first three days. Serena secured the year-end No. 1 ranking after Dinara Safina pulled out of the tournament with a back injury.
Jankovic broke Wozniacki twice in the first set and then raced out to 4-0 in the second, facing little resistance from Dane, who's making her debut in the elite event.
"I just came out playing aggressively," Jankovic said. "I really wanted to dictate the points."
Wozniacki won two grueling three-set matches that lasted a combined 5 hours, 48 minutes on Wednesday and Thursday, and looked as if she had simply run out of energy in the hot weather.
"I didn't have anything left," she said. "I definitely feel like I deserve to get past and make it to the semifinals."
After struggling with severe leg cramps on Thursday, Wozniacki said aching stomach muscles affected her serve against Jankovic.
Azarenka looked to be in control but struggled to put away Radwanska, who was playing her first match in the tournament. She had replaced Vera Zvonareva, who had taken Safina's spot. Zvonareva pulled out with an injury after losing to Wozniacki.
Dementieva needed to win to advance, while French Open champion Kuznetsova had nothing to play for but cash. She had her best match of the tournament and never faced a break point.
"I asked Venus before the game, 'Will you give me something if I win?"' Kuznetsova said. "She was like, 'If you win, it's good for yourself.' I say, 'OK, whatever."'
The Russian qualified for the tournament for the fifth time but has never advanced to the knockout round, with a combined round-robin record of 3-12.