American fourth seed Taylor Fritz suffered a surprise first-round exit at Roland Garros on Monday, beaten in four sets by German Daniel Altmaier.
The 2024 US Open runner-up, whose best performance at Roland Garros was a run to the fourth round last year, slipped to a 7-5, 3-6, 6-3, 6-1 loss on Court Simonne-Mathieu.
World number 66 Altmaier, who reached the last 16 in 2020, will next face unseeded Czech Vit Kopriva.
Order of Play | Win with SPAR | Watch Live on DStv
It is the first time Fritz has lost in his opening match of a Grand Slam tournament since the 2022 US Open.