Rafael Nadal's 2021 tennis season was one to forget. A foot injury kept the clay-court legend off the court for months in what was his least productive year on the court in some time.

Nadal earned $1.478 million in prize money for 2021, marking his lowest total in 17 years. The 20-time Grand Slam champion ends the year ranked as the No. 6 men’s tennis player in the world.

With an overall singles record of 24-5, Nadal won two titles in 2021. Nadal won the Barcelona Open in late April, and he defeated top-ranked Novak Djokovic in the finals for the Italian Open championship in May.

One month after his last tournament victory, Nadal was defeated by Djokovic in the French Open semifinals. It ended his streak of four straight championships at Roland Garros. Nadal has won 13 of the last 17 French Open titles.

Nadal didn’t compete in another Grand Slam for the rest of the year. The 35-year-old announced on June 17 that he was skipping both Wimbledon and the Tokyo Olympics in order to take care of his body and prolong his career. On Aug. 20, Nadal said he would miss the U.S. Open and the rest of the 2021 tennis season because of a nagging foot injury.

"Honestly, I have been suffering much more than I should with my foot for a year and I need to take some time ... to find a solution to this problem or at least improve it in order to continue to have options for the next few years," Nadal said.

Before Nadal prematurely ended his season, he was the No. 4-ranked player on the ATP Tour. Nadal fell two spots and trails No. 5 Andrey Rublev and No. 4 Stefanos Tsitsipas going into 2022.

In his first event of 2021, Nadal lost to Tsitsipas in the quarterfinals of the Australian Open.

Nadal last competed in a non-exhibition event at the Citi Open, where he was defeated by Lloyd Harris in the third round on Aug. 5. It’s the only ATP tournament that Nadal has played since the 2021 French Open.

On Dec. 20, Nadal announced that he tested positive for COVID-19. Nadal had previously played in the Mubadala World Tennis Championship exhibition event in Abu Dhabi in his return from his foot injury.

To go along with his 20 Grand Slam titles, Nadal has 88 career singles titles and nearly $125 million in earnings.

Nadal back on court in Abu Dhabi on Friday
Nadal back on court in Abu Dhabi on Friday GETTY IMAGES NORTH AMERICA via AFP / Rob Foldy