Wimbledon marathon man John Isner, who played in the longest match in history at the All England Club in 2010, was forced to quit his second round match after just two games on Tuesday.
The 28-year-old 18th seeded American had to retire against France's Adrian Mannarino with the score at 1-1 in the first set after he injured his knee while serving.
Isner famously defeated Nicolas Mahut at Wimbledon in 2010 in a tie that lasted 11 hours and 5 minutes over the course of three days.
The final set finished at 70-68 in his favour.
Mannarino goes on to face either former champion Lleyton Hewitt or Dustin Brown for a place in the last 16.