Melbourne - Serena Williams survived a sweltering "out-of-body experience" Wednesday, picking up her game when the roof was closed at the Rod Laver arena and preventing Russian domination of the semi-finals of the Australian Open.

The nine-time Grand Slam winner broke the spell in temperatures of 42 degrees and climbing when, under the heat rule, the roof was closed at the end of the first set, which seemed to give Williams new life.

"A little experience helps, but I guess it's me against the Russians," said Williams after rallying from a set and 5-3 down to overhaul Svetlana Kuznetsova 5-7, 7-5, 6-1.

"I knew I was in a lot of trouble, but I relaxed and wanted to fight," she said. "I wanted to go at least three sets. That's when I play my best."

The three-time champion who lifted the Melbourne title in 2003, 2005 and 2007 said conditions on court were so intense at the start, "I must have had an out-of-body experience."

She is to face fourth seed Elena Dementieva, who beat Spain's Carla Suarez Navarro 6-2, 6-2 to join Russian compatriots Dinara Safina and Vera Zvonareva in Thursday's penultimate stage.

Eighth seed Kuznetsova had looked like she would complete the Russian rout, which would have been only the sixth time in Grand Slam history that women from one nation have populated a last-four lineup.

But Kuzy cracked while serving for the victory, losing serve for 5-all and slowly watching her chances melt.

The Russian had little spark in the final set with Williams bolting to the finish line, her match-point opportunity donated by Kuznetsova's 42nd unforced error.

Earlier, Dementieva kept her dream of a possible number one WTA ranking alive as she stormed past Suarez Navarro to reach her first Melbourne semi-final.

"It only took me 10 years to get here," joked Dementieva, who spent just more than 90 minutes playing with the roof open. And she wondered what took so long to close it.

"When you see a forecast [for 44 degrees], the hottest week in a month, why not close the roof - not only for the players, but for the spectators as well?" she asked. "I think, if you have a roof, why not use it?"

The two-time Grand Slam finalist in Paris and New York said she was glad to get the job done against Spain's pocket rocket, who began her run with a second-round knockout of Venus Williams.

"It was very tough to play because of the weather conditions," said the player who stands 15-0 with two titles so far in 2009. "My opponent is very strong physically, a very fit player.

"Playing her for the first time, I didn't know what to expect. Maybe it looked easy, but an hour and a half for 6-2, 6-2 is a pretty long match."

Dementieva is thick in the chase for top ranking honours with the spot now occupied by Serb Jelena Jankovic changing hands on Monday if Dementieva, Williams or Safina could win the tournament.

"Everyone is thinking about the possibility of reaching number one," Dementieva said. "That's an extra motivation for all of us. That's why I guess we're all trying very hard to win this one." (dpa)