World number one Rafael Nadal pulled out of the ATP Tour Finals on Monday after struggling with injury in his 7-6 (7/5), 6-7 (4/7), 6-4 defeat at the hands of David Goffin.
The Spaniard exited the Paris Masters earlier this month with a knee injury and appeared to be in pain towards the end of his opening match at the O2 Arena in London.
"No, I am off," said Nadal. "My season is finished. Yeah, I had the commitment with the event, with the city, with myself. I tried hard. I did the thing that I had to do to try to be ready to play. But I am really not ready to play."
"Is about the pain," he added. "I cannot hold with enough power to keep playing. I tried, but seriously it was a miracle to be very close in the score during the match. It really doesn't make sense."