If there’s an art to managing this, Coco Gauff mastered it Thursday. She readied and waited and readied and waited for her second-round match through one of the damnedest tennis sagas anybody ever saw, the longest match of this French Open (5 hours 26 minutes), a men’s singles match that lasted more than two hours beyond a match point that ended on a wacky net cord.

“Yes, it is [odd],” Gauff said.

Luckily Gauff, familiar to the tennis-viewing eye since age 15, counts among the wily veterans now even though she still hasn’t bothered to turn 20 yet. (It finally happens next March.) She filled her eventual and undramatic 6-2, 6-3 win over Julia Grabher of Austria with ample know-how to get it done in 68 minutes, and she hurried on to the third round where she will play somebody who is actually 16.

How time moves, except for sometimes when you’re waiting for those people before you to finish.

“Yeah, I was warming up,” Gauff said.

And: “But, yeah, I was probably about 70 percent done with my warmup.”

And so: “That net cord match point was crazy.”

And then: “Yeah, it was a long wait.”

The following represents a fraction of all that happened in the rambling, raucous match on Court Suzanne Lenglen between Jannik Sinner, the onrushing 21-year-old Italian ranked ninth in the world, and Daniel Altmaier, the plucky German ranked 79th.

They played a 58-minute first set to a tiebreaker. They played a 73-minute second set to a tiebreaker. They split those. They played a third set through which Sinner breezed. They got to Sinner serving for the match at 5-4 and deuce and then match point in the fourth.

They got berserk.

Sinner primed to win. He spiced a 10-shot point with a gnarly forehand to the corner. He fielded Altmaier’s defensive lob. He let it bounce and smashed an overhead near the middle of the court. He watched Altmaier dig it out and nudge it forward, and he prepped to volley it to an ending, except it ticked the net cord, tricked his racket and hopped on by. “I think each point in tennis has its own story,” Altmaier would say later, “and I think that’s how that match point went, yeah.”

Gauff and Grabher waited. Sinner had another match point two points later. Gauff and Grabher waited. Sinner and Altmaier roamed into a tiebreaker and 3-3 in there before Altmaier won 7-4 to cause a fifth set. Gauff and Grabher waited.

Asked whether she screamed, Gauff said she screamed but was joking. “Yeah, watch the match, to be honest,” she said. “We’re sitting there all in the gym waiting, and then when a set is over, you go back [to the practice court]. I almost fell asleep in the middle of the fifth.”

The middle of the fifth took its winding road to where Altmaier served for the match at 5-4, Sinner led 15-40, Altmaier got it to deuce and Sinner broke anyway, whereupon Sinner served at 5-5 and Altmaier broke Sinner at 15, whereupon Altmaier served for the match at 6-5 and went ahead 40-love, whereupon Sinner rallied to deuce, whereupon the place became a madhouse with the crowd chanting both names.

That last game, the one at deuce, included 16 points, five match points for Altmaier, three break points for Sinner, Sinner making a pose after a gasp of a forehand pass off an Altmaier overhead on the fourth match point and Sinner throwing his racket to the clay after fumbling one of the three break points. Altmaier won, 6-7 (7-0), 7-6 (9-7), 1-6, 7-6 (7-4), 7-5, and the crowd cheered Sinner on his exit, and the crowd cheered Altmaier for so long before his on-court interview that he went ahead and did what any rational person would do.

He sobbed.

“I just love the game of tennis,” he eventually told the crowd.

“What happened . . .?” a question began later to Sinner.

“Yeah, what happened, that’s a good question,” Sinner said.

By now, Gauff ranks sixth in the world. She stands 13-3 in French Open matches, including that run to the final last year when she expected so much of herself that she wept even after losing to a No. 1 player (Iga Swiatek) on a historic winning streak. Gauff manages the clay with such aplomb, her shots hurrying to corners with exemplary oomph and her mind so considerable, that three-time French Open champion Mats Wilander asked her on-court whether she grew up with clay, and Gauff said: “No. I’m a true American. I grew up on the hard courts,” before saying she started coming to France at age 10 to train at Patrick Mouratoglou’s famed academy.

“That’s where my love of clay started,” she said. Even when it’s dry like now with this dry spring in Paris, she doesn’t mind: “I feel used to it, honestly. I think I’m a great mover. I adjust pretty well to the conditions.”

It’s just that sometimes in tennis, of all sports, there’s uncertainty about getting to the court you fancy.

“I was, like, I wish I could see the future because I probably would have taken a nap in the fourth, but obviously, you don’t,” Gauff said. “Then the eating part for me is the hardest because you don’t want to eat like a full meal if you’re thinking you’re going to go on in 10 minutes, but obviously that 10 minutes can turn into 30, then 30 to two hours. So I’m really just snacking the whole time. That’s why on the changeovers I try to eat a lot too. Two bites here and there” — a fruit salad her father, Corey, makes — “just to make sure I stay fueled for the whole match.”

She moves from that puzzle to a different one, to a qualifier, Mirra Andreeva of Russia, born in 2007. The secret to making the third round at Roland Garros at age 16, Andreeva said, is “maybe, as my coach says, to not be like diva, to stay humble all the time.”

Two non-divas collide. “I guess,” Gauff said, “I’ve never thought about my age, to be honest. So yeah, I’ve played a couple of [younger] people — I think two times. This will be my third time playing someone younger than me. Yeah, honestly, the first two times I didn’t even think about it, because when you step on the court, you just see your opponent, and you don’t really think about the personal side of things. You just see forehand, backhand, serve, all the same.”

Sometimes you even get a convenient schedule.