Coco Gauff’s Coaching Change Already Paying Off as Serena Williams’ Childhood Coach Notices Major Fix Ahead of US Open
Coco Gauff’s bold move to replace coaches Matt Daly and Jean-Christophe Faurel with biomechanics expert Gavin MacMillan just before the 2025 US Open is already showing results, with Serena Williams’ childhood coach Rick Macci praising significant improvements in her serve. Macci, who guided Serena and Venus Williams, posted on X on August 21, 2025, lauding the change: “Coco’s serve will be signed, sealed, and delivered. Gavin’s science-based approach is fixing the toss, spine angle, and weight transfer” (@RickMacci). As Gauff prepares to face Ajla Tomljanovic on August 24, this coaching shift could prove pivotal at Flushing Meadows.
Macci’s Praise and Technical Breakthrough
Macci, known for his technical expertise, had long advocated for Gauff to work with a biomechanics specialist to address her serving struggles, which led the WTA with 320 double faults in 2025, including 42 across three Canadian Open matches and 16 in a Cincinnati loss to Jasmine Paolini. He highlighted MacMillan’s impact, stating, “Coco’s second serve will become a grasshopper on steroids” by refining her preparation and cocking phases (@RickMacci). During practice at Arthur Ashe Stadium on August 20, Gauff displayed a tighter spin and smoother motion under MacMillan’s guidance, with analysts noting improved consistency.
Gauff’s Drive and Context
Gauff, seeded third, justified the coaching switch, saying, “I’m looking long-term. I want my game where it needs to be, and I can’t waste time.” Her 2025 season, while featuring a French Open title and WTA Finals win, has been inconsistent, with a first-round Wimbledon loss to Dayana Yastremska and a 6-1, 6-4 Canadian Open upset by Victoria Mboko. MacMillan, who revitalized Aryna Sabalenka’s serve for her 2023 Australian Open title, aims to boost Gauff’s 48.5% second-serve win rate, which trails Sabalenka’s 52%. Gauff told E! News, “New York always brings out my best,” banking on home-crowd energy.
Outlook and Challenges
Macci’s optimism, echoed by fans on X with posts like “Coco’s serve is 🔥 with MacMillan! US Open ready” (@TennisFanUSA, August 21, 2025), contrasts with a Martina Navratilova-led panel favoring Sabalenka and Iga Swiatek. Gauff’s draw offers early tests against Donna Vekic, Magda Frech, and potentially Naomi Osaka, with Madison Keys and Swiatek looming in later rounds. Her resilience, akin to Emma Raducanu’s coaching transitions or Luke Littler’s darts scrutiny, will be key. As Macci predicts, “Coco can be No. 1 with this fix,” her refined serve could counter Mboko’s rise and challenge Sabalenka’s reign, making her a formidable contender for a second US Open title.
