Wimbledon champion Venus Williams outlasted Serbian third seed Jelena Jankovic 4-6, 6-1, 7-6 (7/4) on Wednesday to reach the US Open semifinals, where she will defend family honor against Justine Henin.
US 12th seed Williams fired 60 winners and made 57 unforced errors but struck true when it mattered most, seizing a 5-1 lead in the tie-breaker and winning with an overhead smash after two hours 27 minutes.
"She played unbelievable. She fought well," Jankovic said. "She was better at the end."
World number one Henin ousted Serena Williams in a Tuesday quarterfinal to put herself in the path of elder sister Venus, who is 7-1 lifetime with seven triumphs in a row against the Belgian star entering Friday's showdown.
"I was so disappointed," Venus Williams said. "More than anything she's my little sister. Watching her be upset was hard for me. I've got to play very well on Friday for her."
Henin and Venus Williams, each a six-time Grand Slam winner, have not played each other since Williams beat Henin in a 2003 Australian Open semifinal.
Beating both Williams sisters in the same Slam has been done only once, when Martina Hingis downed Serena in a quarterfinal and Venus in a semifinal at the 2001 Australian Open.
Friday's other semifinal will be an all-Russian affair sending fourth seed Svetlana Kuznetsova against sixth seed Anna Chakvetadze.
Kuznetsova, who's only Grand Slam title came at the 2004 US Open, defeated Hungarian teen Agnes Szavay 6-1, 6-4 in 67 minutes while Chakvetadze reached her first Slam semi-final by beating Israeli 18th seed Shahar Peer 6-4, 6-1.
"She's a favorite in this match. I have nothing to lose. It's easier to play with no pressure," Chakvetadze said. "I'm playing well but I still feel I'm not playing my best. I'm getting better each day. Hopefully I'll be better Friday."
Kuznetsova, who won prior meetings with Chakvetadze in a 2006 Warsaw semi and the 2006 Eastbourne round of 16, said she has never felt so strong so late in a tournament and is playing well enough to match her 2004 title form.
"I just feel so fresh for the semi-final and I'm ready to go and give it my best shot," Kuznetsova said. "Definitely the pressure is going to be more on me but I will still try to stay tough, to play tough."
Venus Williams, who last reached the US Open semi-finals in 2002, won 10 years to the day after her only other US Open third-set tie-breaker victory, which came against Irina Spirlea after a bumping incident on a changeover.
In the tie-breaker, Jankovic sprayed three forehand errors in a row to give Williams a 5-1 lead. Williams hit a forehand volley winner to reach match point, smacked a backhand wide, and then smashed a winner to end it.
After surrendering a break to open the second set, Williams reeled off six games in a row to put herself in command, although neither player managed a break in the third set.
"If I can continue to play like I did in the second set, things will continue to go well for me," Venus Williams said.
Jankovic broke with impressive lob winners in the opening games of the first and second sets, jumping on Williams early each time.
In the first set, Jankovic denied Williams on two break points in the fourth game and then broke the lanky American again for a 4-1 edge. Williams broke back in the sixth game but Jankovic held twice more to claim the set.
Kuznetsova will replace compatriot Maria Sharapova as world number two in Monday's new WTA rankings with Jankovic's loss.
"Definitely I believe in myself," Kuznetsova said. "Next match is extremely tough with Anna. I'm glad there will be a Russian in the final."
Kuznetsova, 22, raced to a 3-0 lead, saved two break points in the fifth game to seize a 4-1 edge and finished off the first set in only 26 minutes.
"I'm so happy with my performance, especially in the first set," Kuznetsova said. "I felt very good."
Szavay, 18, was the first debutante to reach the US Open last eight since Venus Williams a decade ago but failed to become the first Hungarian women Slam semi-finalist.
Chakvetadze, 20, came into the US Open on a high after taking four titles this year, including US Open tune-ups at Stanford and Cincinnati, and was determined to disappoint a crowd primarily pulling for Peer.
"I thought. 'I will die on this court but I will not lose,'" Chakvetadze said.