Venus prepares to defend the family honour

Venus will play Justine Henin in the semi-finals, the player who knocked out her sister Serena

Typical. You wait ages for a Williams sister to come along and then one arrives after another. Justine Henin had not played Serena or Venus Williams for four years until she met the former in Miami in March, but in today's semi-finals of the US Open here she will attempt to become only the second player, following Martina Hingis at the 2001 Australian Open, to beat both sisters in the same tournament.

Twenty-four hours after Serena lost to Henin in the quarter-finals for the third Grand Slam tournament in succession, Venus earned the chance to uphold family honour by beating Jelena Jankovic 4-6, 6-1, 7-6. Remarkably, she has beaten Henin in their last seven meetings, although the most recent was four years ago. Two Russians, Svetlana Kuznetsova and Anna Chakvetadze, meet in the other semi-final.

The third coming of Venus is proving even more extraordinary than her 2005 comeback, when she became the lowest ranked woman (No 16) to win Wimbledon. She topped that by reclaiming the Venus Rosewater Dish two months ago as the world No 31 and has now put together her best run here since 2002.

Jankovic has been the year's most consistent woman player behind Henin, but when Williams plays as she did on Wednesday night the 27-year-old American looks all but unstoppable. She hit nine aces, serving at up to 124mph, belted 60 winners and, most tellingly of all, played 55 of the 213 points at the net. Jankovic, who had beaten Williams in their three previous meetings, came to the net only six times.

One point summed up Jankovic's task. Williams had come forward behind a moderate approach, but she threw herself to her left to return the Serb's attempted passing shot. Her volley was short and she had left a wide gap on her forehand flank, but when the world No 3 went cross-court Venus leapt across to volley a winner. Jankovic, whose sportsmanship is so refreshing, applauded, her face a mixture of admiration and disbelief.

"I think it's nice to be fair, to give credit to the opponent," Jankovic said afterwards. "There's also nothing wrong with smiling. You have to have fun sometimes on the court. I don't think you have to be as serious as some of the players are."

Williams said she had never lost her self-belief through her lean years and wanted to take her Grand Slam titles (six) into double figures. "I look forward to the future because I love winning, I love competing. I love what I do," she said. "I always believe that I'm the one, and when I'm not it really bothers me."

If the first beaten quarter-finalist of Wednesday's night session felt she had been below par – Jankovic agreed she was feeling the effects of her 85 matches (compared to Williams' 45) this year – the second was justifiably satisfied with his performance. Andy Roddick lost 7-6, 7-6, 6-2 to Roger Federer, who recorded his 14th win in their 15 meetings, but the first two sets, in which there were no breaks of serve, were desperately tight.

Roddick, who went on all-out attack from the start, said afterwards: " I'm not walking with my head down. I played my ass off tonight. I played the right way."

For the second year in succession Federer's semi-final opponent will be Nikolay Davydenko, who beat Tommy Haas 6-3, 6-3, 6-4. In the other semi-final Novak Djokovic or Carlos Moya, who played last night, will meet David Ferrer, who beat Juan Ignacio Chela 6-2, 6-3, 7-5.