Since Justine Henin retired, there has been a conspicuous lack of true dominators at the top of the ladies hierarchy. No single woman has since stamped her authority on world tennis, and it is fair to say that Maria Sharapova aside, the Williams brand of power tennis again had many observers stating that only their lack of continuous tournament appearances has prevented them being the top two ranked ladies in the world.

On the men’s tour, world number one Roger Federer has emerged from what some would call a form slump to again compete at the highest levels – claiming two runner-up plates at the two most recent Grand Slams. However, it is the emergence of Spaniard Rafael Nadal as a player able to win Grand Slams other than the French that is the talk of the tennis world. His dominance of Federer at the recent Roland Garros Slam was frightening, and while Federer had more parity at the All England club, he still lost to Nadal on what is the Swiss master’s pet surface.

At Wimbledon, Federer and Nadal have competed in the final the last three years, with the Swiss being a permanent fixture there since his first title in 2003. This year Nadal broke Federer’s stranglehold at the All England Club. The Williams sisters between them have won no less than seven of the prestigious grass court Slam titles – and have taken four runner-up plates.

At Roland Garros, Federer and Nadal have also competed in the final the last three years – with the Spanish clay court master holding the last four titles. The Williams sisters have only appeared in one Roland Garros final – it is their weakest surface, with Serena beating Venus in 2002.

In Australia, Roger Federer’s run of two titles at Melbourne was broken by the Serbian Novak Djokovic. Although to be fair to the Swiss champion, the beginning of 2008 was arguably his worst run of form since he came to dominate men’s tennis. Serena has won the title at the Rod Laver court three times since 2003.

At the hard courts of the US Open, Federer has won four straight titles. However, his Spanish nemesis is still to compete at a final at Flushing Meadows. On present form though, it would be a brave punter that would bet against the Spanish world No.2 breaking that duck. In 1999 the Williams sisters began a run of four titles – two apiece.  However, the last five years has not seen a sister appear in the final of their home slam.

With no disrespect to other top-ranked men, when on form Federer and Nadal are in a different class. Nadal is only 22 and has a long career in front of him, and woe to those if he translates his clay court dominance to other surfaces. He now has five Grand Slams – being undefeated at Roland Garros and holding the record for 81 consecutive winning matches on the red surface. He has now been ranked the No.2 player in the world for over three years.

The Swiss master needs no introduction, with 12 Grand Slams and now being the world No.1 for approaching five years. While he has seen his dominance slated to some degree, only Nadal is at his level. There is no doubt that these two men will go down as arguably the two greatest men’s players in history. Such is their dominance and style that while the tournaments may be too predictable – they are a pleasure to watch and long may their rivalry continue.

The Williams sister are in the top 10 of the world – with Serena being ranked fifth and holding eight Slam titles. Older sister Venus is ranked seven and has seven Grand Slams to her name.

The other woman in the WTA rankings top 10 are Ana Ivanovic, Jelena Jankovic, Maria Sharapova, Svetlana Kuznetsova, Elena Dementieva, Anna Chakvetadze, Dinara Safina and Agnieszka Radwanska. Despite this being the cream of the ladies rankings, there are only five Grand Slam titles amongst them. But these elite of the women’s tour do hold one considerable advantage – with all of them being very young.

They all hold strong records at the Slams, but there is no woman in the top rankings outside of Lindsay Davenport (who, it is fair to say, is past her prime) with the pedigree of the Williams sisters.

They do not play tournaments as much as some of their other competitors, which sometimes leave them short of match practice as well as the ability to accumulate the points in the rankings. If they decide that their Wimbledon success could be a catalyst, they may once again dominate the women’s tour – although while the Federer and Nadal rivalry is compelling, the constant clashing of the Williams girls in finals is not as gripping as either of them may think.