It is not just a string of coincidences that makes the American a strong favorite against her Russian opponent, although there are many of them.

Williams won in 2003, 2005 and 2007 and would love the keep the symmetry going. In each of those previous title years she has had at least one match where she came from behind to win, just like against Svetlana Kuznetsova in the quarter-finals.

And, in each successful year, weather conditions have forced the closure of the roof at Rod Laver Arena, just like this year.

But it's her game that makes the most compelling case for another championship Down Under.

Safina is strong and talented and capable of an upset but Williams should have too much resilience for the younger woman.

Big match nerves could also come into play. Safina struggled in her only major final last year, losing to Ana Ivanovic at the French Open and her temperament has occasionally been called into question.

Williams has proven she has the mentality to win big titles time and

Rafael Nadal's reputation was built by tennis's need. The young Spaniard emerged at a time when the game was desperate for a challenger to Roger Federer, to avoid the men's tour from turning into a one-man show.

Great rivalries are, of course, built on contrast, so Nadal was cast as the physical warrior, the man of passion, supreme strength and iron will to counteract Federer's genius.

All those qualities were on display in Friday's Australian Open semi-final against Fernando Verdasco, as Nadal ground out a marathon five-set victory against one of the hottest players on tour.

But make no mistake, there is genius about Nadal as well.

His manner will never be as effortless as Federer's. Sweating, grunting and fist-pumping are all part of what makes Nadal the player he is.

Yet there are also, with increasing frequency, the kind of jaw-dropping moments that inspire awe in the way Federer has done for years.

One of them arrived at just the right time against Verdasco. As the match

As Roger Federer sat slumped in his chair and London’s evening murk closed around him, the changing of the guard in men’s tennis seemed complete – and permanent.

Rafael Nadal’s thrilling victory in an epic Wimbledon final last summer anointed a new king, even though it took a few more weeks for the top two players in the rankings to officially swap positions.

At that point, and in the weeks that followed, predictions of a Federer collapse were plentiful.

A dismal start to the North American hard court season suggested a man who had shed his aura of invincibility. Even after triumphing at the U.S Open, severe doubts were raised about whether the Swiss master could keep pace with Nadal in 2009, and see off the challenge of Novak Djokovic and Andy Murray.

Those thoughts have been emphatically swept away over the last 11 days and Federer’s 6-2 7-5 7-5 canter past Andy Roddick on Thursday set him up for yet another Grand Slam final.

It will be his 18th appearance in the title game of a

The leading players who petitioned for the Australian Open to be moved back into February have been given a helping hand from the weather gods.

To allow for greater preparation time, stars such as Roger Federer have argued in favor of delaying the tournament in future years.

Yet as temperatures soared to record levels, the weather conditions provided a new and frankly more compelling reason why the event could be better off being staged slightly later.

The mercury rose to an incredible 120 degrees on Tuesday and was still just under the 100 mark at 10 p.m.

Officials were forced to implement the event’s Extreme Heat Policy, which uses a special formula involving air temperature, wind, solar radiation and humidity to determine whether it is safe to play outdoors.

However, that did not pacify Svetlana Kuznetsova, who came within three points of beating Serena Williams but fell away in the third set once the roof was winched across to keep out the blistering sun.

Williams looked

Roger Federer's masterful destruction of Juan Martin Del Potro has lifted the Swiss world No. 2 to the top spot on the Yahoo! Sports Australian Open power rankings.

Rafael Nadal can count himself unfortunate to lose the top spot, as he has yet to drop a set in the tournament. It was impossible, though, to look past Federer's outstanding display at Rod Laver Arena, where he lost only three games in the match against Del Potro.

On the women's side, Serena Williams is bumped from the top position after struggling badly on the way to a third-set victory over Svetlana Kuznetsova.

Elena Dementieva takes her place - and the two women will square off in Thursday's first semifinal.

Men

1. (2) Roger Federer: Magnificent in quarterfinal and looks as good as ever. SF: vs. Andy Roddick.

2. (1) Rafael Nadal: Still hasn't dropped a set and is enjoying the hot conditions. SF: vs. Fernando Verdasco.

3. (3) Fernando Verdasco: Spanish iron man could find Nadal too much to handle. SF: vs. Rafael Nadal.

Andy Roddick has not been this close to a Grand Slam final for two years but given the size of the task he faces he may never have seemed further away.

The big-serving American has been outstanding in the Australian Open so far, cruising through to the final four and knocking off defending champion Novak Djokovic in Tuesday's quarters.

Roddick has every right to be feeling good about his game. Six weeks of intensive fitness training with coach Larry Stefanki was a punishing yet productive way to spend the end of 2008.

Fifteen pounds lighter, his physical levels are now among the strongest on tour and the 26-year-old looks primed for a big year.

When Roddick stepped off Rod Laver Arena to follow the stricken Djokovic, who retired due to severe physical discomfort as temperatures climbed more than 120 degrees on court, it was easy to feel good about his chances of adding to his only Grand Slam, the 2003 U.S. Open.

Within a few hours, though, such an outcome seemed as likely as a sudden

Over the past four years only one man has known what it feels like to break the Grand Slam monopoly of Roger Federer and Rafael Nadal.

Novak Djokovic's victory at the Australian Open last year was the only time in the last 15 Slams that one of tennis' two biggest stars did not emerge as the champion.

Yet as he headed Down Under to defend his title this month, the Serbian world No. 3 has somehow managed to duck under the radar.

Once again, all eyes are on Nadal and Federer and the latest installment of their epic and ongoing battle at the top table of tennis.

That has suited Djokovic just fine. Whereas once he loved nothing more than to seek attention, delighting crowds with his hilarious impersonations of other players, these days he is more circumspect.

The 21-year-old believes he is the player best equipped to compete with Nadal and Federer, especially at this tournament, but would prefer to steer clear of the limelight at Melbourne Park.

Last year he dispatched Federer in three

Despite Andy Murray's exit at the hands of brilliant Spaniard Fernando Verdasco, the men's quarterfinals are still loaded with talent.

Murray was the only top-eight seed who failed to reach the quarters and the tournament is building toward a thrilling crescendo.

Rafael Nadal remains atop the Yahoo! Sports Australian Open power rankings, having hardly been stretched on his way to the last eight.

On the women's side, Serena Williams was fortunate to escape her fourth-round clash with Victoria Azarenka – her 19-year-old opponent took ill after winning the first set.

However, Williams is still very much the woman to beat and has high hopes of adding yet another Grand Slam title to her collection.

Men

1. (2) Rafael Nadal: Twelve straight sets won without even being taken to a tiebreak. QF: vs. Gilles Simon.

2. (3) Roger Federer: Survived a scare but is still a huge title threat. QF: vs. Juan Martin Del Potro.

3. (5) Fernando Verdasco: Big serve is finally matching devastating ground game.