Roland Garros was the first Grand Slam tournament to join the "Open" era in 1968, and since then many tennis greats have graced the famous clay courts, including Björn Borg, Ivan Lendl, Mats Wilander, Gustavo Kuerten, Roger Federer, Rafael Nadal and Novak Djokovic.
https://www.atptour.com/en/tournaments/roland-garros/520/overview