Former US Open champion Argentine Juan Martin del Potro requested treatment after suffering a horrible fall in the first game of his Wimbledon quarter-final against Spanish fourth seed David Ferrer on Wednesday.
The Argentine eighth seed called for the doctor following his tumble on Center Court when he stretched to reach a return while leading 40-15.
The 24-year-old's left leg bent at an awkward angle when he slipped, but it was the left knee, already strapped from a previous problem earlier in the tournament, that the doctor examined closely.
Del Potro was treated for several minutes before finally being allowed to resume playing.
In the other big quarterfinal being played today, Serb Novak Djokovic faces Thomas Berdych in the only match that follows the seeding at Wimbledon.
With the untimely departure of Nadal and Federer, the field is wide open for anyone to take the coveted title.
Djokovic vs. Berdych is a rematch of the 2010 Centre Court semifinal in which Berdych prevailed in straight sets. Djokovic has credited that match with his renewed interest in getting fit and coming back.
"Yes, in some ways it was a low point. I had quite a turbulent five, six months of 2010. The semifinals of Wimbledon came in the right time for me because I felt that was like a springboard for me."
"When you win, everything is great. But especially when you lose big matches, that’s when your character is exposed the most."
The winner of these two matches will face each other to determine the men's semifinals.
Local Andy Murray will face Spaniard Fernando Verdasco in one of the most anticipated matches at Wimbledon. Murray is attempting not to become another of the top seeds to fall to a higher seed player.
Murray's only loss to Verdasco came in 2009 at the Australian Open.
Juan Martin del Potro continues to battle David Ferrer and is up 6-2, 6-4.