The Italian star eased to a 6-3, 6-3, 6-4 win under the new roof on Court Suzanne Lenglen as rain fell at Roland Garros.

Australian Open champion Sinner showed no signs of struggling with his fitness despite missing the recent Rome Open with a hip injury.

The Italian star struck 32 winners and broke Eubanks' serve five times as he set up a second-round meeting with French veteran Richard Gasquet.

"I'm just happy to be back on court. I was injured so very happy to be back here," said Sinner.

"It's a very special tournament for me.

"The hip is good, I'm very happy... The general shape isn't at 100 percent yet so we're trying to build every day."

Sinner is playing only his third tournament since winning the Miami Masters in March, after losing to Stefanos Tsitsipas in the Monte Carlo Masters semi-finals and then withdrawing from the Madrid Open before his quarter-final match.

His victory on Monday took his win-loss record for the season to 29-2.

The 22-year-old is hoping to improve on his best French Open performance -- a run to the quarter-finals on his debut in 2020.

American Eubanks enjoyed a breakthrough Wimbledon last year when he was beaten by Daniil Medvedev in the last eight in five sets, but has now lost seven consecutive matches.