The first player to win 20 Grand Slam titles, Roger Federer of Switzerland, announced his retirement from tennis over 24 hours ago. His longtime adversary Novak Djokovic paid tribute to Federer. "Roger it's hard to see this day and put into words all that we've shared in this sport together. Over a decade of incredible moments and battles to think back on," the Serbian star wrote in an Instagram post. "Your career has set the tone for what it means to achieve excellence and lead with integrity and poise," he added. "Your career has set the tone for what it means to achieve excellence and lead with integrity and poise," Djokovic went on to write. "I know that this new chapter will hold amazing things for you, Mirka, the kids, all your loved ones, and Roger fans still have a lot to look forward to," he wrote, before wishing Federer and his family "much joy, health, and prosperity in the future". Federer made the announcement that the Laver Cup later this month would be his final competition on social media on Thursday. In 2003, when he won the Wimbledon championship, Federer claimed his first grand slam victory. Since then, he has won five US Open championships, eight Wimbledons, six Australian Opens, and one French Open. Only Djokovic and Rafael Nadal, each with 21 Grand Slam victories, have more than the Swiss great. The 41-year-old has been sidelined from competition due to operations and recovery since his last professional encounter at Wimbledon last year. Roger Federer announces retirement from tennis Nadal might not join Federer, Djokovic, Murray for Laver Cup following US Open loss 'Virat is best cricketer on earth, don't expect him to score..,' appeals Brett Lee