Just ahead of the US Open, Coco Gauff made a decisive move by parting ways with coach Matt Daly and bringing biomechanics expert Gavin MacMillan into her team. Known for his scientific approach to tennis technique, MacMillan is now tasked with addressing Gauff’s persistent serving issues, which have plagued her throughout the season. With over 320 double faults recorded this year, the change signals Gauff’s commitment to long-term improvement.
Gavin MacMillan’s Impact on Aryna Sabalenka
MacMillan’s reputation stems from his transformative work with Aryna Sabalenka. In 2022, Sabalenka faced a crisis in her game, recording 428 double faults and struggling to maintain consistency. Under MacMillan’s guidance, she refined her serve mechanics, focusing on fluid weight shifts, wrist angles, and toss control. These adjustments led to a dramatic turnaround, culminating in three Grand Slam titles and a rise to world No. 1.
Why Gauff Chose MacMillan
Gauff’s decision was described as sudden but strategic. She acknowledged the need for a technical overhaul and saw MacMillan’s availability as an opportunity she couldn’t ignore. Despite Daly’s previous success, including guiding her to titles in Paris and Beijing, Gauff prioritized future growth over past achievements. She continues to work with Jean-Christophe Faurel, maintaining continuity while embracing innovation.
The Science Behind the Serve
MacMillan’s approach is rooted in biomechanics, analyzing movement patterns and anatomical efficiency. His work with Sabalenka involved correcting her toss arm position, synchronizing body motion, and reducing unnecessary tension. These principles are now being applied to Gauff’s game, with hopes of achieving similar breakthroughs. Observers have already noted subtle improvements during practice sessions at Flushing Meadows.
Looking Ahead
As Gauff prepares to face Ajla Tomljanovic in the first round, the tennis world watches with anticipation. Her willingness to make bold changes reflects a deep desire to evolve. Whether MacMillan’s methods will yield immediate results remains to be seen, but the partnership marks a new chapter in Gauff’s pursuit of excellence.
Cori Gauff in 2025
At the moment ranked no.3, Gauff played her last match on the 15th of August when she was overcome by world no.8 Jasmine Paolini 2-6 6-4 6-3 in the quarter in Cincinnati (draw).
During this season Coco has an overall 35-12 match record. Gauff has won 2 titles in 2025 in Australia and French Open. The American reached the final in Madrid and Rome.