Follow us on Google Discover Coco Gauff has shown signs of improvement under the wing of newly appointed Gavin MacMillan.
Gauff appointed MacMillan, a biomechanics specialist, as her head coach ahead of the US Open, mainly to correct her serve, having tallied 320 double faults across 48 matches.
Though she suffered a fourth-round exit at Flushing Meadows, the American has gone far in both Beijing and Wuhan with her new coaching team.
While there is still work to be done on her serve, she has shown glimpses of MacMillan’s influence, most notably in her opening match at the Wuhan Open against Moyuka Uchijima, where Gauff did not record a single double fault.
Photo by Robert Prange/Getty ImagesRick Macci makes a prediction about Coco Gauff’s serve
Her recent performances have caught the eye of Serena Williams‘ former coach, Rick Macci, who has seen improvements in her service motion.
In a post on X, Macci said: “Coco now feels the mandatory biomechanical changes to her serve and already is delivering in combat.
“Before she got tips/advice, which was only a reaction to a symptom. Now she understands the origins/ culprits and has rewired the muscle memory.
“Before the double faults/first serves were a mystery, and we will see one of the best serves down the road in tennis history.”
Coco now feels the mandatory biomechanical changes to her serve and already is delivering in combat. Before she got tips/ advice which was only a reaction to a symptom. Now she understand the origins/ culprits and has rewired the muscle memory. Before the double faults/ first…
— Rick Macci (@RickMacci) October 11, 2025
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Coco Gauff’s serving statistics at the 2025 Wuhan Open
In her clash with Uchijima, as well as a total of zero double faults, Gauff fired five aces and tallied a first serve percentage of 85%, while winning 89% of points on first serve.
Against Zhang Shuai in the third round, the 21-year-old hit an additional three aces, and had a second serve win percentage of 82%.
Despite Gauff recording six double faults in round four against Laura Siegemund, she was only broken once by the German during the match.
The two-time major champion’s switch-up in coaching staff has proved to be the correct decision so far, and she will now look to finish the year strong before starting her first full season with MacMillan in her corner.