Back-to-back wins over the Williams sisters have left top seed Justine Henin as a hot favourite for Saturday's US Open final, but she insists she will not underestimate opponent Svetlana Kuznetsova.

The 25-year-old Belgian defeated Venus Williams 7-6 (7/2), 6-4 in a tremendous semifinal on Friday, two days after trouncing the American's younger sister Serena 7-6 (7/3), 6-1 in the last eight.

Kuznetsova, on the other hand, strolled through the weak bottom half of the draw and did not meet a top 10 player until scraping past sixth seed Anna Chakvetadze 3-6, 6-1, 6-1 in Friday's other semifinal.

First problem for Henin will be recovering from her efforts in the 24 hours that separate her from Saturday's final.

"I know I'm probably not going to sleep very well this night because it's going to be a big final tomorrow," she said.

"The adrenaline is still going to be here for a couple of more hours now. I'm older. Tough to recover."

Then there is her opponent, against whom she has a crushing 14-2 winning record.

"It will be difficult that's for sure," she said. "I want to enjoy this moment now, but I know that tomorrow is going to be another day and I have to be a hundred percent focussed on that one.

"I will have to be very, very aggressive. With a lot of determination I believe I can do it."

Kuznetsova stunned the tennis world by winning the 2004 US Open as a little-known 19-year-old, the first Russian to do so, but since then she has struggled at times to maintain her form.

This year though she has been one of the busiest and most consistent of players on the WTA Tour even though she had to wait until the week before Flushing Meadows before winning another title.

New York, she says, brings out the best in her.

"Some players complain about the crowd here, but it's one of my favourite crowds of everywhere," she said.

"It's just kind of show time. The crowd is always crazy. It pumps me up. Many surprises happen and I love that."

The two players are old adversaries, having played each other 16 times since Wimbledon in 2003 and Henin holds a crushing 14-2 advantage in wins.

Kuznetsova though won their last meeting 6-4, 5-7, 6-4 in the semifinals of the German Open in May and Carlos Rodriguez, who has coached Henin throughout her professional career, is wary of the Russian's threat.

"We have to be on guard," he said. "Kuznetsova was the best in the other half of the draw and she will have nothing to lose.

"We know her pretty well and she can give trouble with her huge forehand, but Justine will be ready.

"She is playing incredibly this fortnight and most of all she is enjoying herself."

Rodriguez was referring to the emotional changes that have marked this year for Henin.

She opted out of the Australian Open at the start of the year following her split from husband Pierre-Yves Hardenne and this cleared the way for a reconciliation with her estranged father Jose, elder brothers David and Thomas and younger sister Sarah. Henin returned to the courts with renewed vigour and enthusiasm in February and since then she was won six titles out of the 10 she has competed in including her fourth French Open title in June.

The six-time Grand Slam winner is already assured of finishing the year as world No.1 while Kuznetsova will rise to a career-best second win or lose in the final.