Melbourne - Justine Henin says she is still trying to find the right balance between being too intense and too relaxed as she bids to win her first Grand Slam since making a comeback to the sport.
Henin overcame a determined Nadia Petrova 7-6 (7/3), 7-5 on Tuesday to reach the semi-finals of the Australian Open, where she will play Chinese surprise packet Zheng Jie.
A seven-time Grand Slam winner, the fiercely competitive Henin retired in May 2008 while ranked number one, saying she was burnt out.
But shortly after fellow Belgian Kim Clijsters won the US Open last September after making her own comeback, Henin announced she too would return to tennis.
Ever since she arrived in Australia at the start of January for the Brisbane International, Henin and coach Carlos Rodriguez have been talking about the 27-year-old's new relaxed outlook on life.
She has shown this fortnight that she still has a ferocious will to win, but insists that unlike in the past, off court she is now very different.
The problem is how to keep it that way.
"Well, it's a big challenge, but I think we can find a good deal," she said after her win over Petrova.
"I hope it's not only because it's the beginning, and I'm not going to get crazy again in six months," a smiling Henin added.
"In the past ... in a Grand Slam, I was really in my bubble.
"Now, we just go forward. Like I say, we try many, many different restaurants, I'm more open to a lot of things.
"That's the way I have to keep going, to find the right moment to put the intensity and the concentration (aside) and to get away from that.
"It's a very interesting experience for me this week."
Henin, granted a wildcard to play here, struggled through long matches in her last three rounds, defying her aching body and an injured left thigh.
By contrast Petrova had been in excellent form, highlighted by her 52 minute thrashing of Clijsters in the third round and her win over third seed Svetlana Kuznetsova in the fourth.
There was little between the two players as they went shot for shot on a hot day on the Rod Laver Arena.
Both looked fragile on serve at times, losing their own serve twice each on the way to a first set tiebreak.
But Henin played a brilliant tiebreaker, opening a 6-1 lead and holding on to take the set in 55 minutes.
The loss of the first set seemed to fire up the Russian and she skipped out to a 3-0 lead in the second, breaking Henin twice in the process, only for Henin to claw her way back to get the set on even terms.
Then at 5-4 and Petrova serving, Henin attacked again and the Russian faltered, sending a backhand long and ensuring Henin's passage to the final four.
"I think I've improved a lot in this tournament since in Brisbane," she Henin.
"I haven't been able to play well in the tough moments and this week, in this tournament, I've been able in the last few days to do it.
"Even if I'm getting older, I still have this fighting spirit, and that's a good thing."
Petrova said she would not be surprised if Henin won the tournament.
"She has a good shot -- I mean, she has a really good round in the semi-finals," Petrova said.
"Whoever she's going to face in the final, I'm sure, you know, she has a good shot at it."
Results from day nine of the Australian Open at Melbourne Park on Tuesday (x denotes seeding):
Women's singles
Quarter-finals
Justine Henin (BEL) bt Nadia Petrova (RUS x19) 7-6 (7/3), 7-5
Zheng Jie (CHN) bt Maria Kirilenko (RUS) 6-1, 6-3