American second seed Serena Williams and Russia's world number four Elena Dementieva both reached the Australian Open semifinals but followed different paths in Wednesday's quarterfinals.

Dementieva, a semifinalist at both Wimbledon and the U.S. Open last season, reached the last four after another easy win, dispatching Spanish dark horse Carla Suarez Navarro 6-2, 6-2.

While the American, looking to win her fourth Australian Open crown, had to dig deeper after losing the first set 7-5 to Russian eighth seed Svetlana Kuznetsova.

The roof of the Rod Laver Area was closed after the opening set of Williams' match under the heat policy, which seemed to be in the American's favor as the tough player muscled back into her game en route to her stunning comeback 5-7, 7-5, 6-1 victory.

"I think the roof helped a lot because it was really hot out there. I was just gonna try to go for a third set with the roof open. But with the roof closed, it was definitely helpful," said Williams, describing the heated first set as an out-of-body experience.

"Like I felt I was watching someone play in a blue dress ( Williams's outfit), and it wasn't me, because it was so hot out there. And I kept trying to tell myself that it's not hot."

Dementieva, who had to work hard amid extreme heat on a sweltering noon, complained to the media that the heat policy should be applied ahead of her match, saying that it is not only for the players, but for the spectators as well.

The temperature soared to 41 degrees and it will last until the weekend, which is the hottest week of the month, the weather forecast said.

Dementieva was troubled again by her infamous double faults, committing ten this time, but still mastered her opponent in only one hour and 33 minutes.

The Russian, 27, who is still looking for her first career Grand Slam title, appeared quite efficient on breaking points, converting on four out of five breaking chances, while the Spaniard, seven years the Russian's junior, had to improve on big points performance after failing to make use of any of her ten breaking opportunities.

"Maybe it looks easy. But I think for such a score like 6-2, 6-2, we're playing one and a half hour, which is a pretty long match," the Russian said.

Williams, on the other hand, was given a real scare. Kuznetsova was outclassing Williams in just about every department for the first set and a half, building a 7-5, 5-3 lead, just a game away from becoming the fourth Russian to reach the semifinals, following Dinara Safina, Vera Zvonareva and Dementieva. But it was not to be.

From 7-5, 5-3 down, Williams' trademark aggression returned, as she pummelled serves, returns and down-the-line winners to reel off 10 of the last 11 games of the match.

"I finally started playing a little better at the end of the second set. I felt like I was really off before," Williams said.

"It's really encouraging because the whole tournament I felt I've been off. I was happy because I wasn't playing my best today. I was thinking, 'Wow, this is not my best tennis, or even close to it. '"

Had Kuznetsova won, it would have been the first time in the Open Era that Russian girls made up the entire final four at a major. Australian and American girls had done it previously.

(Xinhua News Agency January 28, 2009)