The Spaniard beat Pablo Cuevas in the third-round of the tournament with heavy strapping on his knee, but then announced he would be unable to play the Serbian qualifier Filip Krajinovic in the next round.
Nadal said that “the pain during the match (on Thursday) was too much.”
He added: “The way that I am today I do not see myself playing three more matches. The knee is always bothering a little bit but sometimes it’s worse.”
However he was reluctant to comment on his chances of playing at the season-ending ATP Finals, where he is slated to be the top seed.
“It is not about London, it is about the longer term” he added.
“I have no idea how much that knee was affecting everything,” she said. “He came up with seven double faults and some of those balls were dribbling halfway up the net.
“You have to think that was because he couldn't push up from that leg. He was different to the player that started the match.”
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