PARIS — In some ways, Coco Gauff is very much a typical 18-year-old, striding into Court Philippe Chatrier for her French Open semifinal on Thursday with earbuds in place, listening to a playlist she explained is "called 'Rap' — and I can't say the next word." And in some ways, she is an old soul, anything but a run-of-the-mill teen — or run-of-the-mill tennis player.

So when Gauff had wrapped up her 6-3, 6-1 victory over Martina Trevisan to reach her first Grand Slam final, setting up a showdown against No. 1-ranked Iga Swiatek on Saturday, the American thought of the recent spate of mass shootings in her home country and wrote in marker on a courtside TV camera: "Peace. End gun violence."

"I woke up this morning, and I saw there was another shooting, and I think it's just crazy. I know that it's getting more attention now. But ... this has been an issue, at least in my head, for a long time, and I definitely think there needs to be some reform put into place," Gauff said.

"I think now especially, being 18, I've really been trying to educate myself around certain situations, because now I have the right to vote and I want to use that wisely."

A willingness to speak out about issues of significance, and a wide-lens view of the world, reflect the sort of maturity that has served her well, especially with so much attention from such a young age.

She won the French Open junior title at 14. She became the youngest qualifier in Wimbledon history and then beat Venus Williams on the way to the fourth round there at 15.

"From what I see on court, she's developing every year, basically," said Swiatek, the champion at Roland Garros in 2020 and on a 34-match winning streak after eliminating No. 20 Daria Kasatkina 6-2, 6-1 on Thursday. "And when I see her, I tend to forget that she's 18." Ah, but she is.

When Gauff arrived in Paris a little more than two weeks ago, she celebrated her recent high school graduation by posing for cap-and-gown photos near the Eiffel Tower while holding her diploma. Now she's the youngest player to reach a major title match since Maria Sharapova won Wimbledon at 17 in 2004.

Gauff has won all 12 sets she's played, although she did not need to navigate the most arduous path to get this. Because of all manner of surprising results and early exits by top players from the bracket, she has faced only one seeded foe, No. 31 Elise Mertens.

Big serves that reached 115 mph against Trevisan, a terrific backhand and a still-improving forehand are the keys to the 18th-seeded Gauff's game.

Trevisan also praised Gauff's defense, likening facing her to hitting against a wall — every ball comes back.

Now, in Swiatek, comes someone who will present a much tougher test. The only Polish player to win a major singles title hasn't lost since February, stringing together five tournaments in a row; only Venus Williams, who won 35 consecutive matches in 2000, has a longer unbeaten stretch this century.

"I'm just trying to treat these matches as any other matches," Swiatek said, "because it is stressful, and I accept that. But I want to keep doing the same work."

The men's semifinals are Friday, with 13-time French Open champion Rafael Nadal playing No. 3 seed Alexander Zverev, and 2014 U.S. Open champion Marin Cilic facing No. 8 Casper Ruud.

With only faint wisps of clouds overhead and the temperature hovering around 75 degrees Fahrenheit (about 25 Celsius), the two women's semifinals followed a similar pattern.

Swiatek-Kasatkina was at 2-all. Then Swiatek claimed 10 of the last 11 games.

Gauff-Trevisan was at 3-all. Then Gauff claimed nine of the last 10 games.

Trevisan is a 28-year-old left-hander who entered the day on a 10-match winning streak, including her first career WTA title at Rabat, Morocco, a week before play began at Roland Garros. She also defeated Gauff the only previous time they played — in the second round in Paris two years ago.

There were brief blips of tension Thursday that had little to do with the score.

Trevisan was surprised when chair umpire Marijana Veljovic cautioned her about grunting — "I always play like this," the Italian said — after the official was asked by Gauff whether it was OK that her opponent's cries of "Ahhhh!" were stretching into Gauff's racket swings.

Gauff questioned Veljovic about a couple of line calls, drawing whistles and boos from spectators who frown on that sort of thing. After one such interaction, Trevisan broke serve to pull even at 3-3. Unbothered, Gauff broke right back to lead 4-3, smacking a backhand winner that brought Mom and Dad out of their seats in the player guest box.

Now there's one match left to determine a champion: the dominant Swiatek against the precocious Gauff.

"I'm in a mindset now like: 'It doesn't matter.' I mean, I'm going to be happy, regardless. My parents are going to love me, regardless. So I'm just going to go into it like another match," Gauff said. "I mean, yeah, it's a Grand Slam final, but there are so many things going on in the world right now, and especially in the U.S. a lot of stuff is happening right now, so I think it's not important to stress over a tennis match."