Djokovic and Murray face giant challenges in Wimbledon semis

Wimbledon 2013 will be remembered as a tournament of shocks but unless giants Juan Martin del Potro and Jerzy Janowicz can chop Novak Djokovic and Andy Murray down to size, Sunday's men's final will be a showdown between the world's top two players.

In a sport that plays on the psychologically vulnerable and demands supreme levels of physical endurance, the consistency of Djokovic and Murray in reaching the business end of Grand Slams is nothing short of remarkable.

When Djokovic takes to Centre Court to play Argentine Del Potro, it will be his 13th successive semi-final at a major, while Murray's match-up against Janowicz will be his fifth consecutive appearance in the last four at Wimbledon.

Should they both win, it will be the third time in the last four Grand Slams that they have met in the final.

Their rivalry has usurped that of Roger Federer and Rafa Nadal as the biggest draw in the sport and with the Swiss maestro and the Spanish matador having been dumped out early, two different faces will contest Friday's semis.

Juan Del Potro, a Grand Slam winner at the US Open in 2009, is hardly an unknown, but Janowicz has emerged from obscurity and will enter the world's top 20 next week.

Both players are imposing figures on court. Poland's Janowicz stands at 6-foot-8 and Del Potro is a mere two inches shorter.

Both have booming serves and heavy duty forehands and both are distant outsiders to cause an upset - bookies have Djokovic a 1-6 favourite to beat Del Potro and Murray is 1-5 to end Janowicz's surprise run.

Del Potro will do well just to make it on court. After a nasty tumble in his third-round match, when he collided with a chair, he has played with heavy strapping around his knee.

His quarter-final against David Ferrer looked like it was going to be over after just five points when the Argentine eighth seed slipped, over-extended the wounded knee and needed a medical timeout.

The emphatic way he came out hitting, however, pummelling forehands past one of the sport's best defensive players, showed that although his movement might be restricted, he remains a major threat as long as the ball is within range.

"I'm not going to put my body at risk," he said. "The doctors tell me with this tape and taking some anti-inflammatories you can play.

"If they say something different, I will think."

He will need to be 100 percent to have a chance against Djokovic.

The only former champion in the last four has a 8-3 winning record against Del Potro, is one of the game's very best returners and will keep him working his wounded limb from start to finish.

Some comfort for Del Potro is that he won their last meeting at the Indian Wells Masters in March as well as the bronze medal match on the Wimbledon lawns at last year's Olympics.

Murray, looking to shed the millstone of becoming the first British man since Fred Perry in 1936 to win the Wimbledon title, faces a similar threat.

Jerzy Janowicz, a qualifier last year who has rocketed up the rankings and beat compatriot Lukasz Kubot in straight sets in the last eight with the help of 30 sizzling aces.

He is Poland's first male Grand Slam semi-finalist and, at 22, is the youngest man to reach the last four at Wimbledon since Murray in 2009.

"I hope Andy will feel some kind of pressure," he said. "I'm sure he will feel some kind of pressure because Great Britain is waiting for the champion of Wimbledon."

The pair have played each other twice with US Open champion Murray winning one and Janowicz the most recent encounter at the Paris Masters in November.

"It will be a very tough match," Murray said. "He has a big serve. He's a big guy with a lot of power. He also has pretty good touch. He likes to hit dropshots and doesn't just whack every single shot as hard as he can."