Big shake-up for Coco Gauff: Parts ways with coach, adds expert behind Sabalenka’s serving revival

Coco Gauff has made a change to her coaching staff just before the US Open, parting ways with her coach Matt Daly and adding biomechanics expert Gavin MacMillan to her team. The two-time Grand Slam champion recently lost the world No. 2 ranking and has seen a downturn in her results since winning the Roland Garros title in early June.

The American was having a great run during the clay-court swing, reaching the finals in Madrid and Rome and winning her second major title in Paris. However, the results have not been with her since then: two consecutive first-round losses in Berlin and Wimbledon left her with a poor showing on grass.

With the start of the American hardcourt swing, it seemed Gauff could bounce back in her favorite part of the year, but she only reached the Round of 16 in Montreal and recently fell in the Cincinnati Open quarterfinals. The 21-year-old star lost a good chance to compete for the Cincinnati title and again showed problems with double faults, totaling 16 in her 6-2, 4-6, 3-6 loss to Paolini.

In fact, Gauff has accumulated 85 double faults in the eight matches since winning the Roland Garros title. That's an average of more than 10 double faults per match, with a peak of 23 in her first-round match against Danielle Collins in Montreal.

According to a report by ESPN, Coco Gauff has decided to part ways with coach Matt Daly, with whom she had worked since September 2024. Daly previously coached Canada's Denis Shapovalov. With Daly, the 21-year-old star won the WTA 1000 Beijing Open and the WTA Finals in 2024, in addition to winning the Roland Garros title this year.

Meanwhile, according to Forbes, Coco Gauff has added a new member to her team: biomechanics expert Gavin MacMillan. MacMillan previously worked with Aryna Sabalenka to solve the Belarusian's similar issues with double faults.

Jannik Sinner's coach and ESPN commentator, Darren Cahill, commented on what the addition of a sports biomechanics expert like the renowned MacMillan could mean for Gauff. “A lot of things add up and this could be a really good relationship,” Cahill recently said on ESPN. “He’s very thorough ….I’ve spoken to him many, many times before and the fact that he’s got experience with different athletes from different sports, both male and female, he uses the new technology, he goes to the video a lot, really breaks down the biomechanics.”

Coco Gauff's painful quarterfinal loss to Jasmine Paolini in Cincinnati marked a low point. In a tournament she had won back in 2023, she seemed to be on a firm path to the final. However, she was once again plagued by double faults and wasted a one-set lead against the Italian. "Sometimes, tennis fans want us to win every week, but it's not that easy," Gauff said. "We play 11 months out of the year. Compared to what happened before my US Open title two years ago, it's easier for me to manage these expectations now.”

The American hit a total of 16 double faults, a problem that ultimately cost her dearly against Paolini. This issue has persisted across several tournaments, and since winning her Grand Slam title, she holds a record of just 4-4, including losses in the opening rounds of Berlin and Wimbledon.

"No one calls my season bad because I won Roland-Garros, and for people, winning a Grand Slam more or less defines whether you've had a successful season or not,” Gauff added in a press conference in Cincinnati. “This is true for me, but also for other players on the circuit. I would say that it's completely normal for a player to be really performing for three or four weeks, then experience a downturn for a month because that's how our season is structured with the sequence of tournaments."