Nadal's much-discussed foot problem could trip up veteran's bid for historic calendar-year Grand Slam

When Wimbledon rolls out the lush green carpet to welcome Rafael Nadal at the championships for the first time in three years this week, it will be the Spaniard's foot, rather than his formidable forehand, that will be scrutinized to the nth degree.

Until recently, not many people had even heard of "radio-frequency ablation treatment"－a procedure which uses heat on the nerve to quell long-term pain.

But it is thanks to that procedure, which the 36-year-old had earlier this month to treat a degenerative condition that affects the bones in his feet, that he is able to turn up at the All England Club ready to target Grand Slam title No 23.

When Nadal rocked up at the Australian Open in January, he had not won a major for 15 months, had been out of action for five months due to his chronic foot pain and admitted that he had considered giving it all up for good.

Even in Nadal's wildest dreams, it is unlikely that the Spaniard could have imagined the sequence of events that would unfold over the following six months.

Despite being troubled on a day-to-day basis by the intense pain and discomfort in his feet, his super-human body somehow managed to carry him through 50 incredible sets at the Australian and French Opens to take his overall Grand Slam haul to a men's record 22－including an eye-popping 14 Roland Garros titles.

"In general, it's just unbelievable what Rafa has achieved," Nadal's great rival Roger Federer, the holder of 20 majors, told Tages-Anzeiger.

"The record of Pete Sampras, which I beat, was 14 Grand Slam titles. Now Rafa won the French Open 14 times. That's unbelievable. He keeps raising the bar. It's gigantic."

Thanks to that unexpected run of success, Nadal arrives at Wimbledon halfway through a calendar-year Grand Slam－a position he has never been in before.

While the sporting world will be willing him to win the third leg of the calendar Slam－a feat that was last achieved in 1969 by Rod Laver－the modest Mallorcan crusader is not driven by records or numbers.

"It's not about being the best of the history. It's not about the records," the 2008 and 2010 Wimbledon champion said recently.

"It's about: I like what I do. I like to play tennis. And I like the competition. What drives me to keep going is the passion for the game, to live moments that stay inside me forever... and play in front of the best crowds in the world and the best stadiums."

During the French Open, there was a lingering fear that every match Nadal played at Roland Garros could be his last.

With age no longer on his side and the medical interventions required just to keep going getting more and more frequent, that sense of the finishing line to his career approaching quickly is unlikely to go away.

A lot of things about Nadal's Wimbledon prospects remain uncertain. Will he last the distance on the slick surface that has been the most punishing for his body? Will he face great rival Novak Djokovic in the July 10 final? Will he be able to leave Wimbledon with his hopes of completing the calendar Grand Slam still intact?

Amid all of those unknown factors, the one thing that is certain is the fans who will turn up in their thousands will cherish every second of the fist-pumping action he provides on court－after all no one knows if this will be his final hurrah on the most famous stage in tennis.

Reuters