CoCo & Co.

NEW YORK—The racquet demolition heard ’round the world may not be all that CoCo Vandeweghe will be remembered for at this year’s U.S. Open. Since that GIF-able moment in her 6-2, 6-1 second-round loss to Bethanie Mattek-Sands, the 45th-ranked American has reached the quarterfinals in doubles with partner Anna-Lena Groenefeld.

That said, it may take a photograph of Vandeweghe holding a championship trophy to replace the visual of her obliterating her poor frame into smithereens.

"I just chalk it up to having a really, really bad day on a really, really big occasion," Vandeweghe’s coach, Craig Kardon, said about the destructive sequence. "It’s not something that I endorse. She needed to do something to get rid of her anger, but that was the wrong way to do it."

Vandeweghe has since channeled her energy into an impressive doubles run. She and Groenefeld have beaten Grand Slam singles champions Sam Stosur and Svetlana Kuznetsova, the 10th-seeded team of Su-Wei Hsieh and Anastasia Rodionova, and two-time Grand Slam doubles champions Andrea Hlavackova and Lucie Hradecka, the No. 7 seeds. Vandeweghe and Gronefeld haven’t dropped a set yet in Flushing Meadows; next up for them is Caroline Garcia and Katarina Srebotnik.

"Ultimately playing more doubles will help your singles, so she’s buying into that," says Kardon, who has been trying to instill the doubles game into the 23-year-old since the two began working together at this year’s French Open.

After splitting with her previous coach, Maciej Synowka, Vandeweghe brought in Kardon at the suggestion of her agency, Lagardere Unlimited. Kardon jumped on a plane two days before her first match at Roland Garros. "I happened to be free. She needed a coach who could go now," Kardon says.

Vandweghe dropped her first-rounder in Paris, but the partnership with Kardon, who has previously worked with Martina Navratilova, Ana Ivanovic, Lindsay Davenport, and Mary Pierce, among others, appears to be bearing fruit.

Despite her early exit in singles at the U.S. Open, Vandeweghe has had her best Grand Slam season to date. She reached the third round of the Australian Open to hit a career-high ranking of No. 32. Then, with Kardon in her corner, she reached her first Grand Slam quarterfinal at Wimbledon. She beat three seeds along the way—No. 11 Karolina Pliskova, No. 22 Sam Stosur and No. 6 Lucie Safarova—and then took out Maria Sharapova to three sets on Centre Court.

"You never know how the coaching relationship with a player will go in the beginning," Kardon says about their time in Europe. "It’s not only just your tennis but you’ve got to be with that person on the road. You have to get along."

"You go through hard times, you go through good times," Vandeweghe says. "You have to have a good personality that meshes together on and off the court. But also you have to have a respect factor from both sides."

Vandeweghe’s success at the All England Club was thanks to two main reasons, says Kardon. “Her game style and the way she plays is the right kind of game style for grass-court tennis, that’s number one. Number two, she just kept really calm and focused throughout the whole tournament.”

As one of the biggest servers on tour, reason number one is self-explanatory: Vandeweghe’s 120-M.P.H. bombs do their most damage on grass. But Vandeweghe’s calm and focus, the second reason, was the result of a number of changes she made to her team, long before this season began.

"I entrusted people to take care of the tennis so I could focus on the fitness and diet," Vandeweghe says. "I surrounded myself with a good group of people at home so all the miscellaneous things would be taken care of."

One of those individuals is Jesse Elis, Vandeweghe’s touring physiotherapist and trainer. The California native met Elis through XSOS, an athletic performance center for training, nutrition, and physical therapy in San Diego. "She comes everyday ready to work so it makes my job easier that she’s wanting to put time in at the gym and on the court," Elis says. "And she’s fun to be around."

There’s also Vandeweghe’s hitting partner and friend, Pete Francis, who has traveled with her throughout the summer. "Having that constant battle and pressure all the time, where you know [Pete’s] going to give you a certain level [everyday], I think is a really big positive," Vandeweghe says.

Francis also sees himself as a calming force, which the fiery Vandeweghe sometimes needs. "I’m the middle man, I’m the calm person of the group," Francis says.

As the for the leader of this family, that’s Kardon, whose coaching philosophy and experience have augmented the discipline that Vandeweghe was searching for. "Craig is the dad," Elis says. "He’s been around the block. He understands what needs to be done. He’s a go-getter, and wears his emotions on his sleeve."

"You’re there to kind of guide them but also discipline," Kardon says. "It’s a trust issue. [Players] have to trust you and respect you otherwise it doesn’t work… I go out on the court every day and I’ll say what I believe in. I’m willing to get fired for saying what I believe in."

So far, so good. The pair will work together throughout the next leg of the season in Asia, with an eye on the future. Next year, Vandeweghe, the daughter of former Olympic swimmer Tauna Vandeweghe, hopes to be part of the Olympic Games in Rio.

"Olympics have always been the biggest goal of mine," Vandeweghe says. "My mom was a two-time Olympian, so even before Grand Slams and things like that I always dreamt of being in the Olympics and representing my country."

Vandeweghe has four Americans above her in the rankings, including Sloane Stephens, who she beat at the U.S. Open. But with guidance from her athletic family, Vandeweghe hopes to add to her actual family’s legacy.