Ahead of the Australian Open, Coco Gauff had nothing but praise for Matt Daly. She asserted, “Matt has helped me with the technical side of things — my serve, specifically, and other things, as well.” With Daly by her side, Gauff secured wins in Beijing, the WTA Finals, and the 2025 French Open. However, following a tenure of less than a year, she parted ways with the grip specialist. In his stead, she brought Gavin MacMillan on board. Yes, he’s the same biomechanics expert who helped Aryna Sabalenka overcome her weak serve. And if you’ve been keeping up with Gauff’s numbers long enough, this decision doesn’t feel hasty at all. 

Despite Daly’s guidance, her struggles with serves continue to haunt her, with her double-fault tally now standing at a whopping 320 (the most in the WTA). And that’s where MacMillan swooped in.

Ahead of the US Open, during a press conference, a reporter asked about her decision to split with Daly and hire MacMillan. Coco Gauff answered, “Yeah, it was a very sudden decision. Gavin became available, and I just felt, you know, this was the best for my game, at least. And I had to go with what I was feeling…” She acknowledged that Daly was a great coach and she loved working with him. However, her current focus is on her long-term game.  Gauff continued, “And you know, I’ve known Gavin has had experience with this before. So, hoping that I can just, you know, take on his knowledge and see what can happen.”

But we have to admit, bringing changes into the technical side of things, just before the US Open, was pretty huge. Yet, Gauff was unflinching. She said, “I mean, a tournament is a tournament. Like, I hate losing regardless of where I am. [If] This was a 250, I would just feel just as crazy to do it. And yeah, I felt like this is a good opportunity because I mean, I don’t have that many points to defend honestly in this part of the season.” She’s currently ranking at #3 in the WTA with 7874 points, and securing the US Open could catapult her to #1 in the world. 

Thereafter, another reporter asked her if there was any hesitation on MacMillan’s part right before the US Open. Coco Gauff wasted no time and replied, “No, he’s a confident person.” Of course, there’s a lot of pressure on them. But she decided for the best. She continued, “I’m doing what’s best for my game. And I feel like as athlete, I can be like, yeah, won French Open, I made finals back-to-back, quarters of Australia.’ I can be like, ‘Okay, I’m doing fine, and continuing playing the way that I’m playing. But I know where I wanna see my game in the future. And I’m not gonna waste my time playing the way I don’t wanna play.’” 

But what do renowned coaches like Rick Macci think of this move? Did Coco Gauff actually make the right decision by changing her coaches right ahead of the US Open? 

Serena Williams’ ex-coach weighs in on Coco Gauff’s big decision before the US Open

According to Serena Williams’ former coach, Rick Macci, Gauff made the right decision by swapping coaches. Taking to X, he wrote, “Corey Gauff just made the best decision in his life for Coco [Gauff]. By hiring Gavin MacMillan, this can be solved real quick and make her serve click. What she hears will be 100% different from anything in the past. He knows the issue and understands joint angles and soft tissue. Career changer! This is not only a game changer for Coco hiring Gavin MacMillan, but a major league career changer.”

The coach believes that this change is going to take Coco Gauff to “another level.” Previously, Macci had confessed that he was interested in working with the #3 WTA star. He emphasized that it all has to be done with the backing of science and “from a biomechanical point of view.” After all, he believes that Gauff’s serving troubles can be corrected within an hour! 

Now, the question is, can Gavin MacMillan manage to improve Gauff’s serve in time? Can we actually get to see a version of Coco Gauff that steers away from double faults at the US Open singles? To watch her progress at Flushing Meadows, head to EssentiallySports’ live blog of the slam.