Jan. 23 (UPI) -- Rafael Nadal -- the world's No. 1 men's tennis player -- has retired from the Australian Open after injuring his leg.
Nadal took the first set 6-3, before falling 6-3 in the next set. He won the third set 7 (7)-6 (5) and fell 6-2 in the fourth set. The match lasted about 3.5 hours.
"Unbelievable performance from both of us and really unfortunate for Rafa," Cilic said after the match. "He's an unbelievable competitor, always gives his best, and very unfortunate for him to finish this way."
Nadal has retired just twice in 264 grand slam matches. His previous withdraw came at the 2010 Australian Open in a quarterfinals matchup against Andy Murray.
Tuesday's withdraw came after losing a point on a return from Cilic. Nadal could not catch up to the ball. He then walked up to the chair umpire and shook his hand before leaving the court. He bounced a tennis ball on the ground in frustration.
Cilic moves on and faces Kyle Edmund of Britain in the semifinals. The 6-foot-6 Creation is ranked No. 6 in the world.
"Sadly leaving the #ausopen tonight. I'll get an MRI tomorrow morning to see what is the injury. Thanks for the support to all my fans," Nadal tweeted after the match.
Nadal last won at Melbourne in 2009.