World number two Daniil Medvedev reached the French Open second round with a comfortable win but 14th seed Denis Shapovalov made a surprise exit.
US Open champion Medvedev, 26, won 6-2 6-2 6-2 against Argentine Facundo Bagnis, ranked 103rd.
The Russian reached his first quarter-final at Roland Garros last year - having lost in the first round the four previous times.
He had been unsure of his participation after a hernia operation in April.
"I love Roland Garros, especially since last year. I hope this year I can go further," said Medvedev, who will meet Serb Laslo Djere or Lithuanian Ricardas Berankis next.