PARIS — Ah, the French Open, the time of year when a certain question is asked repeatedly by American tennis fans: Why can’t the country’s players, particularly the men, find success on red clay?

Now comes along Jack Sock, a 22-year-old born in Nebraska and currently residing in Florida, who unabashedly calls the slow stuff “my favorite surface.”

Yes, that’s right, even though there are not many red clay courts in the United States — Sock first encountered them in Europe — and even though, at first glance, they’re considered less-than-ideal for players who thrive on speedy serves and forehands. Sock and another U.S. man, 16th-seeded John Isner, both fit that description. Both won first-round matches at Roland Garros on Tuesday.

“This just suits my game very well,” Sock said. “I’m able to take my time and kind of maneuver the ball around. Movement is another big part of my game. I feel like on the clay, I get to a lot of balls.”

He did just that Tuesday on bullring-shaped Court 1 during a 7-6, (7), 6-2, 6-3 victory over Bulgaria’s Grigor Dimitrov, who was a Wimbledon semifinalist last year and was seeded 10th in Paris, making him the top man to lose so far.

Dimitrov’s take?

“Jack played his game,” he said.

Cleanly, too. Sock hit 30 winners and made only 18 unforced errors (10 fewer than Dimitrov) and saved all six break points he faced.

Not traditional clay-court tennis, necessarily. But it worked.

“I may have been one of the first to really like it,” said Sock, who won his first ATP singles title last month in Houston on green clay.

The 6-foot-10 Isner, who beat Italy’s Andreas Seppi 7-5, 6-2, 6-3, is also learning to like the crushed dirt.

“A lot is said about clay and how it’s a defensive surface. It’s sort of, I would say, a misconception,” Isner said.

Four of the seven U.S. men in this year’s field already are gone, as are 13 of the 17 women from the country. Andre Agassi was the last American man to even get to the quarterfinals at the French Open, and that was in 2003.

On the women’s side, second-seeded Maria Sharapova advanced to the third round with a 6-3, 6-1 victory over fellow Russian Vitalia Diatchenko earlier today.

Sock’s win over Dimitrov represented the day’s only loss by a seeded man.