Rafael Nadal of Spain plays a shot in his quarter-final match against Jordan Thompson of Australia during the Brisbane International tennis tournament in Brisbane, Australia, on Jan 5, 2024. (PHOTO / AP)

Rafael Nadal is unsure if he will compete at the upcoming Australian Open after his defeat to Jordan Thompson in the Brisbane International quarter-finals on Friday, during which the Spaniard left the court on a medical timeout.

Nadal was making his comeback in Brisbane after spending almost a year on the sidelines with a hip injury, sustained during his second round defeat to Mackenzie McDonald in last year's Australian Open.

The 37-year-old, winner of 22 Grand Slams, did not compete again last season after having surgery in June, and was using the Brisbane International as a warm-up for the Australian Open which begins on Jan 14.

Australia's Jordan Thompson hits a return against Spain's Rafael Nadal during their men's singles match at the Brisbane International tennis tournament in Brisbane on Jan 5, 2024. (PHOTO / AFP)

"I hope I can train next week and play the Australian Open, but I'm not 100 percent sure," Nadal said after his 5-7 7-6(6) 6-3 defeat.

Nadal, however, did not wish to make excuses or play down his opponent's achievement.

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"What matters now is that I've been able to play three matches in Brisbane. My opponent played very well and you have to give him credit," the Spaniard said.

"I don't think it's the time to talk about that (degree of pain during the match). I have to leave satisfied and congratulate the opponent. We'll see how I wake up tomorrow and the day after."

Rafael Nadal of Spain reacts between games in his quarter-final match against Jordan Thompson of Australia during the Brisbane International tennis tournament in Brisbane, Australia, on Jan 5, 2024. (PHOTO / AP)

Nadal said the pain is in the left hip, which caused him to miss so much time away from the court, but it may not be the same issue.

"The pain is in the same place, but I feel like it's a bit more muscular because of the tiredness.

"Last season it was the tendon and the feeling was completely different because I felt it a lot more. Today I didn't feel anything, what happens is that being the same place you get more scared."

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Australia's Jordan Thompson (left) and Spain's Rafael Nadal gesture after the former's win at their men's singles match during the Brisbane International tennis tournament in Brisbane on Jan 5, 2024. (PHOTO / AFP)

Nadal has won the Australian Open twice, in 2009 and 2022, and is still hopeful of making this year's tournament, but does not expect to be challenging for the title.

"I hope it's just that I have a strong muscle after several days of playing and a tough match like this with Thompson," Nadal said.

"I already said that my goal was to be competitive in a couple of months."