Rafael Nadal went to Australia planning to play in the upcoming Australian Open, but he cast some doubt about that Friday.

Nadal lost to Australian Jordan Thompson on Friday in the quarterfinals of the Brisbane International in a three-set marathon that lasted almost three-and-a-half hours. Afterward, the Spanish legend said he is "not 100 per cent sure of anything" because of discomfort in his left hip that he experienced during the match.

Against Thompson, Nadal couldn't cash in on any of his three match points in the second set as the Australian prevailed 5-7, 7-6 (6), 6-3. It was just Nadal's third match in nearly a year with most of 2023 lost to a hip injury and subsequent surgery.

Nadal took a medical timeout after five games in the third set.

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The new development comes just ahead of start of the Australian Open in Melbourne on Jan. 14. Nadal has won two of his 22 Grand Slam titles in Australia.

"I hope to have the chance to be practicing next week and to play Melbourne," the 37-year-old said. "Honestly, I am not 100 per cent sure of anything now. Then, the next couple of days, let's see how I feel. If I don't feel well, then we are going to do a test and we are going to check it.

"I feel the muscle tired. It is not the same like last year at all because when it happened last year, I felt something drastic immediately. Here I didn't feel anything."

Nadal said the location of the issue is worrisome.

"The only problem is, because the place is the same, you are a little bit more scared than usual. In an ideal world, it is just the muscle supercharged after a few days of effort and a very tough match."