Jack Draper was beaten by Dutch qualifier Jesper de Jong as the British campaign at the French Open got off to an inauspicious start.
Draper, 22, is 35th in the world but lost 7-5 6-4 6-7 (3-7) 3-6 6-3 to 176th-ranked De Jong on day one at Roland Garros.
The British number two struggled on serve and was broken nine times as De Jong punished him.
He made too many unforced errors and showed his frustrations after a double fault handed over a 5-3 fifth-set lead to De Jong, who served out after four hours six minutes for the biggest win of his career.