The greatest clay court tennis player in the history of the open era is calling it a career this month.

Spaniard Rafael Nadal, 38, revealed last month that he is retiring from tennis after this month’s Davis Cup concludes.

Read more: Rafael Nadal Retiring From Tennis

Both of Nadal’s greatest rivals, 24-time Grand Slam winner Novak Djokovic of Serbia and 20-time Grand Slam winner Roger Federer of Switzerland, have now weighed in with lengthy tributes to their longtime on-court nemesis, and longtime off-court friend.

Read more: Tennis Superstar Novak Djokovic Reacts to Rafael Nadal’s Retirement

While Djokovic reacted quickly to Nadal’s decision, Federer waited a bit. He finally took to his social media platforms to celebrate Nadal with a touching tribute this week, ahead of what could wind up being Nadal’s final match ever.

Nadal is suiting up for his native Spain this month in Malaga. Team captain David Ferrer picked Nadal to represent the country in their country’s quarterfinal clash on Tuesday.

The 22-time Grand Slam champion, currently the world No. 154, lost in straight sets, 6-4, 6-4, to the No. 80-ranked player in the world, Botic van de Zandschulp of the Netherlands. If Spain doesn’t win its next two matches against the Dutch in this round, that defeat to van de Zandschulp will mark Nadal’s final match of his career.

“Let’s start with the obvious: you beat me—a lot,” Federer conceded. “More than I managed to beat you. You challenged me in ways no one else could. On clay, it felt like I was stepping into your backyard, and you made me work harder than I ever thought I could just to hold my ground. You made me reimagine my game—even going so far as to change the size of my racquet head, hoping for any edge.”

In their 40 head-to-head meetings between 2004-19, Nadal comes out ahead, 24-16, including a 10-4 record in Grand Slam encounters. Nadal, nicknamed “The King of Clay” for a reason, boasts a 14-2 record against Federer on clay courts, and an 8-6 record on hard courts. Federer went 5-1 on indoor hard courts against Nadal and 3-1 on grass.

“After the 2004 Australian Open, I achieved the #1 ranking for the first time. I thought I was on top of the world. And I was—until two months later, when you walked on the court in Miami in your red sleeveless shirt, showing off those biceps, and you beat me convincingly,” Federer added. “We were both at the start of our journey and it’s one we ended up taking together. Twenty years later, Rafa, I have to say: What an incredible run you’ve had. Including 14 French Opens—historic! You made Spain proud… you made the whole tennis world proud.”

Both Federer and Nadal were longtime world No. 1s in tennis, as was Djokovic. From July 2005 through mid-August 2009, Federer and Nadal were the Nos. 1 and 2 players (often toggling between both spots). Nadal ultimately finishes his run having served 209 weeks in the ATP’s pole spot. Of the three, only Djokovic remains anywhere near the mountaintop at this stage. Federer retired two years ago, but injuries had essentially stalled his legendary career years prior.

“And then there was London—the Laver Cup in 2022. My final match,” Federer noted. “It meant everything to me that you were there by my side—not as my rival but as my doubles partner. Sharing the court with you that night, and sharing those tears, will forever be one of the most special moments of my career.”

In addition to Nadal’s 22 Grand Slam titles, he has won 70 other ATP career men’s titles, for a stunning 92 total.

The 6-foot-1 southpaw won a record 14 French Opens, plus five US Opens, two Wimbledons, and two Australian Opens, making him one of just four men ever to finish a double “Career Grand Slam” in singles, meaning he’s won all four Grand Slam championships at least twice. He also won an Olympic gold medal in 2008.

“Rafa, I know you’re focused on the last stretch of your epic career,” Federer wrote. “We will talk when it’s done. For now, I just want to congratulate your family and team, who all played a massive role in your success. And I want you to know that your old friend is always cheering for you, and will be cheering just as loud for everything you do next.”

Read more: Novak Djokovic Ousts Rafael Nadal from Men’s Singles Competition

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