Coco Gauff describes the quick but life-changing mindset shift that's helping her play the best tennis of her career at the US Open

• Coco Gauff is headed to the fourth round of the 2023 US Open, matching her best result at the Slam.
• The 19-year-old American credits her stellar play to a more relaxed and joyful mindset on the court.

NEW YORK — Coco Gauff is playing the best tennis of her career.

And, crucially, she's having fun doing it.

The 19-year-old American has blazed through her segment of the 2023 US Open women's singles draw. She took down German qualifier Laura Siegemund, Russian teen Mirra Andreeva, world No. 32 Elise Mertens, former world No. 1 Caroline Wozniacki, and heavy hitter Jelena Ostapenko en route to the semifinals.

This year's run in Flushing Meadows marks her best-ever result at her home Grand Slam and makes her the first American teenager since Serena Williams to reach the final four of the US Open.

But it's a lack of emphasis on those results that she credits for her stellar play so far in New York City.

"I feel confident in my preparation, and I feel confident in my execution," Gauff told Insider. "I hope everything works out. At the same time, I'm not too worried if it doesn't."

"I'm really just enjoying the process of having a tennis career, the ups and downs," she added with a smile. "I know I'm up right now, and I know I'm going to experience a down. Hopefully not this week, but it could happen."

An incredible debut at 15 years old led Gauff to the heights of her sport — and mounting pressure

Gauff seems to be competing like she has nothing to lose, returning to the carefree brand of tennis she played when, at just 15 years old, she upset seven-time Grand Slam champion Venus Williams in the first round of Wimbledon.

With millions of dollars in endorsements invested in her success and tens of thousands of fans flocking to her matches, Gauff started to feel an undue pressure to perform.

That pressure sapped much of the fun from the sport she loved. Realizing that perfection is unattainable and failure is inevitable is, in Gauff's words, "really where the mindset has changed."

"I realize that everybody loses, even the best of the best," she said. "I think that I really have to apply those mistakes and learn from those mistakes and apply it into future matches."

"Before I would think too much on a loss and let that loss affect me for some weeks," Gauff added. "Now I'm just doing really well bouncing back."

New faces in Gauff's box are offering the 19-year-old some levity

The Florida native added two new faces to her coaching squad earlier in the summer: coaches Pere Riba and Brad Gilbert.

The pair helped catalyze a shift in perspective that allows her to play more freely, Gauff said. Gilbert, in particular, is apt to "say something completely random" while the teen is practicing, offering her some levity in moments when she might otherwise succumb to the pressure.

"It's just little things like that that made me realize that tennis is serious, but it's not as serious as sometimes my head makes it out to be," Gauff said. "I really should enjoy it out there."

It seems to be helping. Gauff won two of her four career WTA singles titles last month. At the Citi Open, she beat a trio of top-20 players on her way to hoisting the trophy. Later, at the Cincinnati Masters, she took down world No. 1 Iga Swiatek in a thrilling three-set semifinal before besting then-No. 17 Karolína Muchová in a straight-set final.

Now, she is breezing into the US Open semifinal and looks unstoppable.

"I have a lot of joy in me but I just seem to bottle it up when I play," Gauff added. "Now I'm really just having fun and laughing and smiling, and I think it's making tennis more enjoyable."

How she shifted her mindset so quickly

Many players have tried, and struggled, to do the same. World No. 1 and four-time Grand Slam champion Iga Swiatek — who, as of next week, will fall from her spot atop the rankings — said after her fourth-round US Open loss to Ostapenko that she found the weight of expectations "a little bit stressful, and it shouldn't be."

While the 22-year-old Pole previously told Insider she's "really working hard to not think about" the pressure on her shoulders, she noted Sunday that "sometimes when you force yourself not to think about stuff, the result is the opposite."

Gauff admitted she used to struggle with the pressure herself, but she said Tuesday that "just putting my life into perspective" has made all the difference.

"I used to think negative things like 'Why is there so much pressure, why is this so hard, blah, blah, blah,'" Gauff told Insider. "I realize in a way it's pressure, but it's not. I mean, there are people struggling to feed their families, people who don't know where their next meal is going to come from, people who have to pay their bills. That's real pressure, that's real hardship, that's real life."

"I'm in a very privileged position," she added. "I'm getting paid to do what I love and getting support to do what I love. That's something that I don't take for granted."

She learned from friend and NBA star Jimmy Butler that mentality is key

The change is palpable, not just on the scoreboard but in her energy and demeanor on the court. Even Miami Heat superstar Jimmy Butler, a tennis enthusiast who has fostered a friendship with Gauff, apparently noticed the difference.

During practices ahead of the US Open, Gauff said Butler told her mom that "he can really see the joy in me again in playing and enjoying the competition." She noted that she admires the way the six-time NBA All-Star's "mentality makes his game even better."

"You have people that are talented and don't have the mentality — I think he has the talent and the mentality," Gauff said. "It's just taking him even further. That's something I learned from."

"And honestly, that's part of the reason for that switch I had in the last couple weeks," she added. "People think some incredible thing happened, but realistically between two weeks or between Wimbledon and the next tournament I played, nothing could have really changed that much. It was really just the mental thing."