Chilly weather and low-flying planes failed to throw Kim Clijsters off course today as the Belgian overcame Poland's Agnieszka Radwanska 6-3 7-6 to reach the Australian Open semi-finals.
Clijsters, a Melbourne finalist in 2004, underlined her billing as tournament favourite in a scrap against 12th seed Radwanska in unseasonably chilly conditions at Melbourne Park.
Roaring fly-overs from the Roulettes aerobatics display team over Rod Laver Arena to celebrate Australia Day did little to help the players in a quarter-final that rarely set pulses racing.
"It was a little scary," former world number one Clijsters said of the planes. "They seemed to be flying pretty low. They were loud."
Clijsters said she would not underestimate second seed Vera Zvonareva in the semis, despite having thrashed her 6-2 6-1 in last year's US Open final.
"Hopefully I can bring my best tomorrow," said the three-time grand slam champion, who played with taping on her leg to protect a tight hamstring. "Everything has to be better. (Zvonareva) was really disappointed after I played her at the US Open.
"She used to really have moments where she could really be out of it sometimes. A lot of us players really enjoyed watching her sometimes go a little crazy out there," added Clijsters.
The Belgian traded breaks at the start with Radwanska in their quarter-final before she took the first set in 29 minutes.
Radwanska forced a tiebreak in the second, but Clijsters quickly snuffed out the danger to seal it 7-4 with a bullet of a backhand that the Pole could only flap wide off the line.
Clijsters, who hit 37 unforced errors, warned that world rankings would count for little when she and Russian Zvonareva clash in the semi-finals.
"It's just a number," she said. "I just try to be the best out there."