I hate to retire, says a devastated Nadal

New York - The defending champion looked up at his guest box and indicated something was wrong

Nadal felt the pain sear into his right knee early in his US Open semifinal, on what he called "a bad movement.". 
The defending champion looked up at his guest box and indicated something was wrong. He tried to continue. Eventually, he could not. "That was not a tennis match at the end. Just one player playing, the other staying on one side of the court," Nadal said. "I hate to retire, but staying one more set out there, playing like this, would be too much for me." 
A trainer put tape below that joint after the match's seventh game. At the next changeover, Nadal pulled off the tape. Then, in the second set, Nadal took a medical timeout for a fresh taping. By the end, he was walking with a bit of a hitch in his gait. When he approached the chair umpire to complain about a late call from a line judge, Nadal mentioned in passing that he was going to quit. Soon enough, he did.