Rafael Nadal has suffered a number of career-threatening injuries in the past yet a bad blister on the Spaniard's hand could be all Roger Federer needs to gain a vital advantage in their Australian Open semi-final on Friday.
The 27-year-old Nadal has been forced to play the season opening grand slam with strapping across his left hand due to the sore, which is painful enough to compromise his aggressive style of play.
Holding the racket is not a problem and he remains able to hit his powerful topspin forehand but the world number one has found it increasingly difficult to control his serve as the tournament has progressed. "Serving with this injury leads to problems with the rest of my game," he said.
"When you lose confidence with one shot, an important shot, then you are not able to feel comfortable about the rest of your shots.
"I will try to improve that. If not, I won't have a chance of being in the final."
That Nadal has identified such an innocuous injury, given his creaky knees have been bothering his scampering play for years, as a potential key to winning his semi-final shows how aware he is that Federer may be playing as well as ever.
The 32-year-old Swiss had a terrible 2013, winning just one tournament and falling to sixth in the rankings.
He entered the Australian Open with his lowest seeding at a season opening grand slam since 2002, when he was ranked 13th in the world.
Last year's performances allowed pundits to suggest the Swiss's time had come.
He had reached only one grand slam semi-final since claiming a 17th major title by beating Andy Murray at Wimbledon in 2012 and was losing more games to players outside the 'Big Four' than he had previously.
In the past 10 days at Melbourne Park, however, Federer has appeared to be close to his free flowing best, none more so in his fourth round victory over France's Jo-Wilfried Tsonga and then in Wednesday's quarter-final against Murray.
"It's an amazing result for me to be in the semis again. This one feels different because of the tougher times I've had in slams, Wimbledon, at the U.S. Open," the four time champion at Melbourne Park said.
"I definitely sensed that... I am back physically.
"I'm explosive out there. I can get to balls. I'm not afraid to go for balls.
"Of course, last year at times I couldn't do it, but the important thing is that I can do it now."