Switzerland's Roger Federer attempts to return serve to Croatia's Marin Cilic during their second round match on day 5, of the French Open tennis tournament at Roland Garros in Paris, France, Thursday, June 3, 2021. (AP Photo/Michel Euler)

Switzerland's Roger Federer, right, gives Croatia's Marin Cilic a pat on the back as they meet at the net after Federer defeated him in their second round match on day 5, of the French Open tennis tournament at Roland Garros in Paris, France, Thursday, June 3, 2021. (AP Photo/Michel Euler)

Switzerland's Roger Federer plays a return to Croatia's Marin Cilic during their second round match on day 5, of the French Open tennis tournament at Roland Garros in Paris, France, Thursday, June 3, 2021. (AP Photo/Michel Euler)

Switzerland's Roger Federer serves to Croatia's Marin Cilic for their second round match on day 5, of the French Open tennis tournament at Roland Garros in Paris, France, Thursday, June 3, 2021. (AP Photo/Michel Euler)