For 19-year-old João Fonseca, the opponent he can’t seem to shake isn’t on the court. It’s a chronic back injury that has plagued him since birth, and it’s threatening to derail his Australian Open before it even starts.

The 19-year-old has not competed since falling to Karen Khachanov at the Paris Masters. With the Australian Open fast approaching, uncertainty lingers as his back issue clouds his decision on whether he can take to the court in Melbourne Park.

Fonseca addressed the media during his Adelaide International press conference and confirmed his withdrawal. “Unfortunately, I’m not able to play here. It’s difficult to make this decision,” he said. He explained that training had shown progress, but his condition was still uncertain ahead of the Australian Open.

Fonseca admitted his recovery remains incomplete. “I felt those days that we were practicing, every day feeling a little bit better, but it’s difficult to say that I’m a hundred per cent,” he said. His focus now is entirely on regaining full fitness.

Through this, the Australian Open remains his priority. “We are trying our best to recover a hundred per cent to play the Australian Open, which is our main goal,” Fonseca said. He confirmed no final decision has been made on his participation.

However he remained optimistic despite the setback. “That decision is not made. We want to play, we think that it’s going to be possible,” he said. For now, recovery takes precedence as Adelaide slips away.

Fonseca also explained the nature of his back issue. “I was born with something in my back and sometimes it’s more tight,” said Fonseca. He revealed that the condition has followed him for much of his life.

“I already had a stress fracture five years ago, but it’s something that it’s going to be in my body, so I need to deal with it,” he added. Medical scans have offered some reassurance but not certainty.

“We did an MRI, and it’s nothing very serious, but can be serious, so we want to be a hundred per cent to play,” he said. Caution is guiding every decision as the season begins.

Fonseca’s rise has been rapid. Ranked outside the top 100, he won the Canberra Challenger and qualified for the Australian Open last year. In his Grand Slam main draw debut, he stunned No. 9 seed Andrey Rublev and later claimed his first tour title in Buenos Aires.

He went on to win the ATP 500 in Basel and captured the 2024 Next Gen ATP Finals. He reached a career-high World No. 24 in November. Now, fitness matters more than form. His Australian Open hopes remain uncertain, but if healthy, his talent is never in doubt.

Joao Fonseca eases concerns over back issues during 2025 Paris Masters

Even before withdrawing from Adelaide and Brisbane, João Fonseca had spoken about his back issues last year. The concern first surfaced when he was preparing to face Karen Khachanov at the Paris Masters.

At the time, Fonseca was questioned about doubts surrounding his fitness. He was also eager about the challenge ahead. Despite the uncertainty, he showed confidence in his mindset and preparation before stepping on the court.

“I think it has been a great experience for me to be able to change my mindset so quickly,” Fonseca said. He highlighted the mental challenge of competing shortly after a title win and adjusting to rising expectations.

“It is not easy to win a first round a few days after becoming a champion in a tournament,” he added. “I am very proud and satisfied with how I have mentally managed this new situation for me.”

During that Paris Masters match, Fonseca required multiple treatments from the physiotherapist. Back pain troubled him throughout, but he remained optimistic about his condition and ability to compete at a high level.

“I will be ready for the next match,” he asserted. “I felt the area was a bit loaded, but it’s nothing a good physiotherapist can’t solve.” His words reflected confidence despite the physical discomfort.

Now, after reaching near the peak of his rise in 2025, the delay to start 2026 feels concerning. His talent is unquestioned, but fitness remains the priority. 

One question now lingers: will Fonseca feature at the Australian Open this year?