Rafael Nadal may forfeit final match as retirement plans close to being blown apart

has admitted that he could give up his last professional match.

The 38-year-old recently , where Spain will face the Netherlands in the quarter-final.

to face Botic van de Zandschulp in the singles. But he has now explained why he may not "be on court" for his planned showdown.

The 22-time Major champion is currently competing in his penultimate tournament at the Six Kings Slam exhibition in Saudi Arabia. The countdown to Nadal's retirement is ticking, as Spain faces the Netherlands at the Davis Cup on November 19.

The former world No. 1 was named in Spain's line-up and team captain David Ferrer previously confirmed that Nadal was hoping to play one of the two singles matches.

But Nadal has now cast doubt over whether he will take to the court outside of doubles.

"Emotionally, I'm sure I'll be ready. Physically and in terms of tennis level, there remains a month left to prepare," Nadal said of his upcoming retirement match.

While Nadal has been working with his match against van de Zandschulp in mind, he is prepared to step back if he feels he can't win.

The Spaniard added: "I will try to be in good shape to help the team to win. If I don't feel ready for the singles, I'll be the first one to say.

"Be 100 per cent sure, I will not be on court if I don't feel ready to win my match."

If Nadal doesn't compete in the singles at the World Cup of men's tennis, fans are still hoping to see him in the doubles alongside Carlos Alcaraz.

For now, the 38-year-old is focused on the Six Kings Slam, where he lost to Alcaraz in the semi-final. Nadal will now face his long-time rival Novak Djokovic one final time in the third-place playoff on Saturday.

Ahead of their final showdown, he said: "To have Novak in front, it's like a nostalgic thing.

"We've played each other a lot, so it'll be fun to play each other again one more time in this match. Hopefully we can create a good show and good level of entertainment."