Following his shock loss to Viktor Troicki at the Shanghai Masters on Wednesday, Rafael Nadal cast some doubt over the rest of the year.
The Spaniard was sent packing in straight sets by the world number 31 in just the second round, his 14th loss of the season.
The result has forced Nadal to take stock of his form, which led to several negative responses in the post-match press conference.
"I don't know what's going to happen in the next couple of weeks," said the 14-time major winner.
"It's something that I need to think about. I cannot say now what I'm going to do during the next month. I'm not sure about my calendar. I'm not sure about the things that I need to do to try to be 100 percent ready for next year.
"Maybe I'm going to play in Basel in two weeks. So it's not the day and not the moment to analyse all these kind of things."
— Ladbrokes (@Ladbrokes) October 12, 2016
Nadal added that perhaps competing is not the best way to return to form, but rather hard work on the practice court.
"Sometimes keeping (on) competing is not the solution," added the 30-year-old.
"Sometimes the solution is to practice and stop and have a process of training. And maybe that's an opportunity to do it."
Nadal is set to compete at the Swiss Indoors Basel from October 24, where he would be the second seed behind Stan Wawrinka.