Aleksandar Kovacevic did plenty of tossing and turning on Sunday night before finally settling in for what he thought was about six hours of restless sleep.

He had good reason to be nervous. Kovacevic, who is 24 years old and the world’s 114th-ranked player, had a Facnoon tennis date in the first round of the French Open with Novak Djokovic, the winner of 22 grand slam singles titles.

The only person with a more daunting assignment perhaps was Flavio Cobolli of Italy. Cobolli, who is 21 and ranked 159th, survived the qualifying tournament last week, only to be rewarded with an opening-round confrontation with Carlos Alcaraz.

It didn’t go so well for either of the unknowns.

It is a truism of tennis that the top players hate playing the first round of a grand slam. Anything but a cruise to victory is cause for concern. Also, there is always the possibility of epic failure in the form of a loss to someone few have heard of.

Whatever discomfort Djokovic and Alcaraz may have felt walking onto the courts at Roland Garros on Monday, they mostly managed it with ease.

Kovacevic, who lost to Djokovic 3-6, 2-6, 6-7 (1-7), had a pretty good idea of what that felt like, too, even though he lasted more than two hours on the court with a player he grew up idolizing.

Kovacevic had a particularly winding journey to his date on the French Open’s center court with Djokovic.

His father, Milan, immigrated to America from Serbia to pursue a doctorate in computer science from UCLA. His mother is from Bosnia and Herzegovina, and Kovacevic grew up on Manhattan’s Upper West Side, about 500 yards from the green clay of the Central Park tennis complex.

In ninth grade, he still wasn’t good enough to play singles for Beacon High School, a public school in Midtown, even though he was spending afternoons training at the John McEnroe Tennis Academy on Randall’s Island.

Things started to click after he left Beacon to train in Florida. At a tournament one summer, he played a top junior who was planning to attend the University of Illinois. His opponent told him he should join him at the school, so he did, even though he didn’t have much interest in college. By the time he finished five years later, he was ranked in the low 400s and figured he would give pro tennis a shot.

On Monday, Kovacevic made his grand slam debut against Djokovic on the main court at Roland Garros, Philippe Chatrier.

When he was six, his parents brought him to watch an 18-year-old Djokovic win an early-round match at the US Open.

He has pictures to prove it, and he has tried to incorporate elements of Djokovic’s game into his own.

“Where I am in my career, like it shouldn’t be so crazy to me that I’m playing some of these guys,” he said. “But, you know, the little kid in me, I’m standing in Chatrier in front of a packed crowd, playing the best player to ever pick up a racket. It’s something that you got to take in for a second, but also push away and try to focus and play.”

Cobolli was in an elevator, still feeling good about qualifying for his first main draw grand slam match, when he looked at his phone and saw that his opponent was Alcaraz. He said he closed his eyes, ran his hand through his hair, and thought, “Oh no.” He lost 0-6, 2-6, 5-7.

Now that Cobolli has seen up close what the best looks like, he said he understands better what he must do to compete — hit the weight room, he said with a grin as he pushed in at his chest with his hand. And get better at tennis.

Hope springs eternal for him as it does for so many of the Kovacevics and Cobollis in the game. Just over two years ago, Alcaraz’s ranking had three digits, too.