Stanislas Wawrinka has admitted that he will face "one of the biggest challenges in tennis" when he takes on Roger Federer in the quarter-finals of Wimbledon on Wednesday.
SW19 will host its first ever all-Swiss quarter-final when the fellow countrymen go head to head tomorrow, with Federer looking to take one step closer to his eighth Wimbledon crown.
The 17-time Grand Slam champion suffered a loss of form last season, but Wawrinka believes that his best tennis is played at the All England Club and compared his dominance of the event to that of Rafael Nadal at the French Open.
"When you play Roger at Wimbledon, when he's fit and confident and feeling well, it's one of the biggest challenges in tennis," Wawrinka told reporters.
"It's like playing Rafa in the French Open. Those guys have been playing their best tennis at those two tournaments for many years."
The winner of their quarter-final will face either Milos Raonic or surprise package Nick Kyrgios in the semis.