Tennis legend Roger Federer and other big names from the sport made a glamorous appearance at the invitation-only Rolex Ambassadors Concert. The event, held under the patronage of French President Emmanuel Macron, celebrated the 150th anniversary of the legendary Palais Garnier opera venue in the French capital.Federer was joined by several other top-rung tennis athletes, including former No. 1s Stefan Edberg, Ana Ivanovic and Garbine Muguruza. The list of sporting guests also included Swiss ski racer Lara Gut-Behrami and Formula-1 star Jenson Button. The festivities included classical music, ballet and other displays of high art.Christian Dior : Front Row - Paris Fashion Week - Haute Couture Spring Summer 2023 - Source: Getty View this post on Instagram Instagram PostMuguruza, who retired from tennis last year, posted a series of stunning pictures and visuals from the event. The Spanish star, who frequently updates her social media followers about the latest goings-on in her life, turned up to the event in an elegant black dress."Unique and incredible night at the @Rolex Ambassadors Concert celebrating the 150th anniversary of Palais Garnier," the multiple-time Grand Slam winner captioned the post.Notably, the Parisian event was held days ahead of the second Grand Slam of the year in the French city. Roger Federer's appearance at the Rolex event has caused speculation that the Swiss maestro may attend Roland-Garros for a special event honouring Spanish legend Rafael Nadal. View this post on Instagram Instagram PostNadal, who bid an emotional farewell to the sport last year, has won 14 of his 22 Grand Slams on the Parisian red clay. Notably, Federer had wrapped up his legendary career with a loss in doubles alongside Nadal at the Laver Cup in 2022.What has Roger Federer been up to since retirement?Fedrer at the Laver Cup 2022 - Source: GettyRoger Federer, widely considered one of the greatest to have picked up a tennis racket, retired from the sport in 2022. Since then, the 20-time Grand Slam champion has been busy with numerous pursuits outside the world of tennis.Last month, the Swiss maestro attended the golf Masters event, one of the four Majors in the sport. Northern Ireland's Rory Mcllroy won the event, completing his career Grand Slam in golf. Congratulating the 36-year-old, Federer wrote on Instagram: "The energy, the setting, and the level of play were truly something special. Huge congrats to @rorymcilroy on winning the green jacket. Thanks to everyone who made the experience so memorable." View this post on Instagram Instagram PostThe Swiss great has also been working to upgrade education and infrastructure for children through his 'Roger Federer Foundation.' Earlier this year, the tennis legend visited South Africa to promote his foundation's 'School Readiness Initiative' in South Africa.