Rafael Nadal's chronic foot injury explained as tennis icon reveals he was in 'constant pain' for 19 years

Rafael Nadal has revealed that a devastating foot injury meant that he spent nearly his entire career in chronic pain.

There's no doubt, Nadal is not only one of the most popular tennis players of all time, but he's also one of the best.

Between his first major win at the 2005 French Open and his retirement 19 years later, the Spaniard won 22 Grand Slam singles titles - with Novak Djokovic the only man to win more.

Nadal's success has gone on to inspire millions of tennis players across the world, including current world no.2 Carlos Alcaraz, who frequently credits his countryman as his childhood hero.

But perhaps the most impressive part about Nadal's career is that he achieved everything while dealing with a chronic foot injury that threatened to end his playing days.

At just 19 years old, Nadal was diagnosed with a rare condition called Mueller-Weiss syndrome after breaking his foot during the 2005 Madrid Open final, only months after winning his first major.

The syndrome is a rare, progressive foot condition that leads to chronic pain and the gradual development of a flatfoot deformity.

“I’ve had to make decisions about my health, where you are on the borderline between right or wrong," Nadal said in a new Netflix series reflecting on his career.

"But if I hadn’t explored all that, I probably would have had 10 fewer grand slams, I'm not saying one or two, I'm saying 10 or 12, this is the reality."

Central to these decisions was Nadal's foot injury, which the tennis star admitted was 'the origin of all my problems' during an interview with the BBC.

"I had to stay over-positive, over-determined, always ready to try to find a solution to keep being competitive and find a way to be on court again," he said.

"I went through, a couple of times in my career, a long process of injuries, but I think I was ready to accept that moment, to tolerate the frustration and to keep working with hope and passion.

"The key was the suffering was less than my passion and my happiness for what I was doing."

How did Rafael Nadal play despite suffering from a rare medical condition?

Throughout his career, Nadal was treated by specialist Dr Ernesto Maceira, who claimed that the condition was caused by the Spaniard's intense training during his childhood.

Although the condition threatened to end Nadal's career before it had even really started, a specialist insole suggested by Maceira allowed him to continue.

The only thing was, he had to do so while in constant pain.

"Tennis became a race against time," said Nadal.

"Always having the doubt in my head of, 'how long can I last with this foot?' I never knew how long my career would last.

"I always thought, 'maybe it's the last year, so there's no time to stop'."

Due to the insole, Nadal suffered several other issues, forcing him to withdraw from both the London Olympics and the US Open in 2012 due to tendinitis in his left knee caused by the insole.

"My knee was destroyed. The tendon basically had a hole in it," Nadal said.

"Having to play with an insole throughout my entire career threw the rest of my body out of whack."

This knee pain then led to Nadal taking anaesthetics to manage the pain alongside various anti-inflammatories, which allowed him to go on and win several other major tournaments, claiming nine more in 2012 alone.

But once again, Nadal revealed that this didn't come without a cost.

"I have two small perforations in my intestines - small perforations that can come from too many painkillers," he said.