<p>An Australian Open that began in a heatwave and contained seismic shocks aplenty ended with Stanislas Wawrinka defeating Rafael Nadal to further undermine the superiority of the so-called big four in men's tennis.<br /><br /></p>.<p>In reaching the final after missing last year's tournament Nadal has cemented his world No 1 ranking and will be hard to shift from the summit but below him the landscape is changing. <br /><br />Novak Djokovic, whose bid for a fourth consecutive Australian Open title was thwarted by the inspired Wawrinka, remains No 2 but both Andy Murray and Roger Federer are falling, to numbers six and eight respectively.<br /><br />There are mitigating factors in Murray's case because he missed the final third of last year because of a back surgery which, as proved in his loss to Federer, will require time before he regains his former strength and power.<br /><br />Federer, who played beautifully to reach the semis, was outplayed by Nadal and the suspicion remains that while still majestic at his best, his chances of adding to his record haul of 17 Grand Slam titles are receding. Wawrinka's wonderful fortnight in Melbourne has propelled him to third in the rankings, making him Switzerland's number one after a career spent in Federer's shadow.<br /><br />At number four is burly Argentine Juan Martin del Potro, who before Wawrinka's defeat of Nadal, was the last player to muscle into the Grand Slam winners' club dominated for the past decade by Federer, Nadal, Djokovic and more recently Murray.<br /><br />Del Potro's second-round exit in Melbourne can be seen as a blip and with his injury woes behind him he will be dangerous at all the remaining Slams this year. Melbourne semifinalist Tomas Berdych, at number seven, will also take heart from Wawrinka's breakthrough after regularly reaching the business end of Grand Slam tournaments, only to fall short against the big guns.<br /><br />Spain's David Ferrer will slip from three to five in Monday's ranking list and while he will continue to hustle and bustle, his career looks unlikely to include a major title.<br />Although the quartet of Nadal, Djokovic, Murray and Federer will, for now, continue to be the first names brought up when talking of the main challengers at the big tournaments, the gap between them and the rest is shrinking. Wawrinka, still at the peak of his powers at 28, is the spearheading the assault with Del Potro and Berdych in close support.</p>
<p>An Australian Open that began in a heatwave and contained seismic shocks aplenty ended with Stanislas Wawrinka defeating Rafael Nadal to further undermine the superiority of the so-called big four in men's tennis.<br /><br /></p>.<p>In reaching the final after missing last year's tournament Nadal has cemented his world No 1 ranking and will be hard to shift from the summit but below him the landscape is changing. <br /><br />Novak Djokovic, whose bid for a fourth consecutive Australian Open title was thwarted by the inspired Wawrinka, remains No 2 but both Andy Murray and Roger Federer are falling, to numbers six and eight respectively.<br /><br />There are mitigating factors in Murray's case because he missed the final third of last year because of a back surgery which, as proved in his loss to Federer, will require time before he regains his former strength and power.<br /><br />Federer, who played beautifully to reach the semis, was outplayed by Nadal and the suspicion remains that while still majestic at his best, his chances of adding to his record haul of 17 Grand Slam titles are receding. Wawrinka's wonderful fortnight in Melbourne has propelled him to third in the rankings, making him Switzerland's number one after a career spent in Federer's shadow.<br /><br />At number four is burly Argentine Juan Martin del Potro, who before Wawrinka's defeat of Nadal, was the last player to muscle into the Grand Slam winners' club dominated for the past decade by Federer, Nadal, Djokovic and more recently Murray.<br /><br />Del Potro's second-round exit in Melbourne can be seen as a blip and with his injury woes behind him he will be dangerous at all the remaining Slams this year. Melbourne semifinalist Tomas Berdych, at number seven, will also take heart from Wawrinka's breakthrough after regularly reaching the business end of Grand Slam tournaments, only to fall short against the big guns.<br /><br />Spain's David Ferrer will slip from three to five in Monday's ranking list and while he will continue to hustle and bustle, his career looks unlikely to include a major title.<br />Although the quartet of Nadal, Djokovic, Murray and Federer will, for now, continue to be the first names brought up when talking of the main challengers at the big tournaments, the gap between them and the rest is shrinking. Wawrinka, still at the peak of his powers at 28, is the spearheading the assault with Del Potro and Berdych in close support.</p>