Novak Djokovic joined the wave of tributes for his great rival Rafael Nadal as he announced his retirement from tennis on Thursday. Nadal, winner of 22 Grand Slams, ends a career considered one of the greatest the sport has ever seen. He dominated tennis for almost two decades alongside Djokovic, who has won 24 Grand Slams, and 20-time Grand Slam winner Roger Federer, collectively referred to as the “Big 3”.

Nadal is expected to retire after appearing for Spain in the Davis Cup final in November. This would mean Djokovic will be the only remaining member of the Big 3 to remain active. However, the 37-year-old Serbian remains at the top of the men’s tennis chain and is currently ranked fourth in the ATP rankings.

Federer paid tribute to Nadal in a reply to the post in which the Spaniard announced his retirement, and has since added a series of images to his story about the 22-time Grand Slam champion. Djokovic has now written his own tribute.

“Rafa, one post is not enough to express the respect I have for you and what you have done for our sport. You have inspired millions of children to start playing tennis and I think that is probably the greatest achievement anyone could ask for,” Djokovic said in a lengthy post on Instagram.

“Your tenacity, commitment and fighting spirit have been taught for decades. Her legacy will live on forever. Only you know what you had to endure to become an icon of tennis and sports in general. Thank you for pushing me to my limits so often in our rivalry, which has shaped me the most as a player. Her passion for representing Spain has always been remarkable.”

Serbia did not qualify for the Davis Cup final but Djokovic said he would be there to pay his respects. “I wish you the best possible farewell in Malaga with the Spanish Davis Cup team. I will be there in person to pay respect to your distinguished career,” he said.

Djokovic and Nadal are known to have played some of the most intense matches of the last 20 years, finishing first at the 2006 French Open. Nadal had won that match. The last game between the two also took place at the Olympic Games in Paris in Rolland Garros. This time Djokovic beat the Spaniard comprehensively.