Greek tennis star Stefanos Tsitsipas has revealed that he learned of his grandmother's death just minutes before his epic five-set French Open final loss to Novak Djokovic on Sunday.

In an Instagram post early Monday morning, the 22-year-old dedicated his first Grand Slam final to her after Djokovic overturned a two-set deficit to win 6-7 (6/8), 2-6, 6-3, 6-2, 6-4 and secure his 19th Grand Slam title.

"Five minutes before entering the court my very beloved grandmother lost her battle with life. A wise woman whose faith in life, and willingness to give and provide can't be compared to any other human being that I have ever met," Tsitsipas wrote of the grandmother on his father's side.

"It's important to have more people like her in this world. Because people like her make you come alive. They make you dream."

Tsitsipas is widely seen as the natural heir to the sport's "Big Three" of Djokovic, Roger Federer and Rafael Nadal but, after receiving the bad news, he said there are more important things in life than winning trophies.

"Life isn't about winning or losing. It's about enjoying every single moment in life whether that's alone or with others," he wrote.

"Living a meaningful life without misery and abjection. Lifting trophies and celebrating wins is something, but not everything."