Coco Gauff was tight on her forehand and shaky on her serve — perhaps the only thing in her game in which she lacks confidence — during Monday’s first-round match on the opening day of the U.S. Open.

There was no giddy crowd packed into Louis Armstrong Stadium at Billie Jean King National Tennis Center in New York, none of the typical roar of support the 16-year-old from Florida might have otherwise enjoyed when she saved three match points against Anastasija Sevastova late in the third set. There was only the thundering of jets flying to and from LaGuardia Airport overhead.

A wily veteran capable of fooling opponents with spin and drop shots, No. 31 seed Sevastova beat Gauff, 6-3, 5-7, 6-4, to hand the teenager her earliest loss in four career Grand Slam appearances. With the win, the Latvian added to an already impressive résumé in New York: Sevastova made the quarterfinals in 2016 and 2017 and reached the semifinals in 2018.

After a months-long pause from large-scale matches and nothing but a first-round loss at the Western & Southern Open last week under her belt, Gauff battled internal demons Monday, double-faulting 31 times, holding her palms to the sky or clutching her head after many of them. She had her serve broken seven times and grew frustrated early in the second set despite playing solidly in the first.

But more than a year after she announced her arrival in major fashion with a run to Wimbledon's fourth round, her tennis may not be what fans remember about Gauff's summer of 2020.

Like Naomi Osaka, who won in three sets in the late match at Arthur Ashe Stadium on opening day, Gauff found her voice as a public figure this summer. Osaka, who was raised in the United States but plays for Japan, used her leverage as the highest-paid female athlete in the world last week when she prompted the Western & Southern Open’s full-day halt in solidarity with NBA players who refused to play in protest of social injustice.

Gauff's moment came months ago, when she was unexpectedly handed the microphone at a protest in Delray Beach, Fla.

“I was 8 years old when Trayvon Martin was killed,” Gauff said in early June, off the cuff. “So why am I here at 16 still demanding change?”

She hasn’t been able to compete on tour all summer, but Gauff’s development from teen phenom to powerful voice was as startlingly quick as her rise up the tennis ranks.

“This summer I learned a lot about myself,” Gauff said. “I learned that I can overcome a lot of things on and off the court. I still hope I can be that way and use my platform in that way. I feel like especially [with] my generation, [it] has been popular, I guess, to speak out, not be afraid to use our voice. I think that just has something to do with it because other young people my age are also using their voice. I’m not as afraid to use it.”

Gauff is confident her development on the tennis court will come along as well; she now prepares for the French Open, which begins Sept. 21. She said taking time off didn’t hurt her progress on court — she was able to fine-tune aspects of her game she doesn’t usually get to — but the lack of match experience did.

“That’s what I need on tour,” Gauff said. “I’m playing against people older than me who have been in more situations, difficult situations, than I have. The biggest thing is I just need experience.”

That experience was one of Sevastova’s primary advantages Monday. After a roiling second set that featured a handful of mini-tantrums, the 30-year-old converted her fourth match point by hammering Gauff’s forehand until she sent a ball into the net.

Sevastova moves on to face Marta Kostyuk of Ukraine in the second round, another deep U.S. Open run still very much in play. She praised Gauff during her virtual news conference, noting that the American improved as the match went on.

“I wish I would play like this when I was 16 years old,” Sevastova said.