Defeat to seventh seed Hurkacz casts doubt over whether clay-court icon Nadal will play at the upcoming French Open, where he has won a record 14 titles.
"I have Roland Garros in just two weeks and a half... I need to prove myself if I am able to push my body to the limit, I need to push to feel myself ready for what's coming," Nadal told reporters.
The 22-time Grand Slam singles champion has recently returned to the circuit after a long absence due to injury.
Spaniard Carlos Alcaraz says he will form a dream team with his legendary compatriot Rafael Nadal in the men's doubles at the Paris Olympics later this year "if everything goes well."
On the women's side, Iga Swiatek was made to sweat in her 4-6, 6-0, 6-2 victory over Brazilian lefty Beatriz Haddad Maia, as she dropped her first set of the tournament and needed two and a half hours to reach a second consecutive Madrid semi-final.
"Now I'm enjoying. Let's see how I wake up tomorrow. Playing at home means everything to me, just try my best to keep dreaming."
Nadal's reward is a last-16 clash with the 30th-seeded Jiri Lehecka on Tuesday.
Rafa Nadal continued his return to form as he defeated Alex de Minaur 7-6(6), 6-3 in the second round of the Madrid Open on Saturday.
Nadal, a 22-time Grand Slam champion, will be 38 in June and has made just a handful of appearances since January 2023 due mostly to a hip injury.
Nadal was also 16 when he played the event in the Spanish capital for the first time.
The 37-year-old, a 22-time Grand Slam champion, said that he is far from being in top form and that he is only playing against American Darwin Blanch in the first round of the Madrid Open on Thursday as a personal sacrifice.
The 22-time Grand Slam title winner, back on court this week after three months on the sidelines, battled well but eventually crumbled against the hard-working world number 11 from Australia.
The 22-time Grand Slam champion had not played a competitive match since January but eased past the 62nd-ranked Cobolli in 85 minutes to reach the second round.
Nadal's return a few weeks ahead of the French Open raises hopes the Spaniard will be able to compete in Paris, where he is a record 14-time winner.
Tennis superstar Rafael Nadal said Monday returning to action at the Barcelona Open is a "gift" and he wants to enjoy every moment of what he expects to be the last year of his career.
The 22-time Grand Slam winner has played just once, in an exhibition match, since he felt a hip injury flare-up during a quarter-final defeat by Jordan Thompson in Brisbane on the eve of the Australian Open.
Rafael Nadal will make his return to ATP competition for the first time since January when he plays Flavio Cobolli in the Barcelona Open next week.
"First training... with the hope of being here these days before the start of the tournament. I'm here to see how it goes... with the desire to try to play," wrote Nadal on social media, alongside a picture of the Spaniard sitting courtside with his rackets.
Rafa Nadal's withdrawal from the Monte Carlo Masters has cast doubt over the 22-times Grand Slam champion's participation at the French Open, but Novak Djokovic said he is still hoping for a final chapter in their storied rivalry.