updated 11:47 p.m. ET Sept. 5, 2007

NEW YORK - So expressionless and serious-minded all night, Venus Williams waited to crack a smile until her victory was complete.

That’s when Williams simply could not help but grin — as she walked to the net for a handshake, as she waved to the crowd, as she spoke about reaching her first U.S. Open semifinal since 2002.

And, certainly, as she thought about getting a crack at the player who eliminated her sister.

Way down Wednesday night, Williams turned her game on when she needed to and was stronger down the stretch, beating No. 3-seeded Jelena Jankovic 4-6, 6-1, 7-6 (4) in the U.S. Open quarterfinals.

Next up is a semifinal against No. 1 Justine Henin. Know this: Venus Williams watched Henin beat Serena Williams on Tuesday and wants to right the wrong.

“I wasn’t happy with that result at all. I was sad that she lost. I didn’t like to see her so upset,” Venus said. “I definitely have to try to win for Williams.”

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The other semifinal has 2004 Open champion Svetlana Kuznetsova against No. 6 Anna Chakvetadze in a matchup between Russians.

Against Jankovic, the older Williams took a while to find the mark, falling behind by a set and a break. But by the end she was playing as well as she did en route to winning Wimbledon in July for her sixth Grand Slam title.

Jankovic made four bad mistakes to allow Williams to take control in the decisive tiebreaker.

“We had some long points, and I was the one making the errors. I maybe was a little bit excited,” Jankovic said. “I thought that it will go in, but it didn’t.”

The 12th-seeded Williams ended it with a swinging forehand volley, an appropriate conclusion given that she made 55 trips to the net, winning 39 of those points. Jankovic was far less aggressive, pushing forward only six times.

Williams dictated play in general, finishing with a whopping 60-17 edge in winners, and after the last one, her face muscles finally relaxed with joy.

“I like to laugh after the match, especially if I won,” she said. “I try to stay focused, in the zone.”

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Speaking to the spectators afterward, Jankovic said: “First of all, I want to say, ’Well done,’ to Venus. She deserved to win. She was better at the end.”

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