Coco Gauff recently made a shocking change to her coaching team as she fired Matt Daly, and joined forces with Gavin MacMillan ahead of the US Open. In light of this, the American’s former coach Brad Gilbert came to her defence amidst criticism about switching coaches often.Gauff and Gilbert began their partnership in August 2023. The youngster excelled under his tutelage, winning the US Open, her maiden Grand Slam title, as well as the Washington Open and Cincinnati Masters. However, the pair parted ways a year later in August 2024, after a string of disappointing results.Now, after Coco Gauff switched coaches yet again, a fan on X asked Gilbert for his opinion on the tennis star, writing,“Coco seems like such a nice gal - balanced - (no pun). How common is it to change coaches so often? My guess it happens a good deal throughout the spectrum of ranked players.”In response, Gilbert defended the 2025 French Open champion, explaining,“It’s a results business, she actually hasn’t switched that much.”Brad Gilbert @bgtennisnationLINK“It’s a results business, she actually hasn’t switched that much.”Gauff and Matt Daly started working together in September 2024. The pairing saw results immediately, with the American being crowned champion at the WTA Finals. She followed this up with her second Grand Slam win at the French Open. However, the 21-year-old has struggled with her results since the clay court Major.She made back-to-back early exits at the Wimbledon Championships and Canadian Open. In her most recent outing at the Cincinnati Open, the World No.3 hit 16 double faults in her quarterfinals match.Now, Coco Gauff has begun to work with Gavin MacMillan, the biomechanical expert who helped World No.1 Aryna Sabalenka overcome her struggles with her serve in 2022.Coco Gauff reflects on her Cincinnati Open campaignGauff in action at the Cincinnati Open 2025 (Image Source: Getty)After a round of 16 exit at the Canadian Open, Coco Gauff began her campaign at the Cincinnati Open on a dominant note, claiming a 6-3, 6-2 win over Wang Xinyu. Up next, she was scheduled to face 32nd seed Dayana Yastremska, but the match was cancelled after the Ukrainian pulled out.For her round of 16 encounter in Ohio, Gauff went up against Italy's Lucia Bronzetti. She won the match 6-2, 6-4. However, the American was unable to maintain this momentum in her quarterfinals match, where she went down to seventh seed Jasmine Paolini.Reflecting on her outing at the Masters 1000 event, Gauff wrote on Instagram,“In the rear view mirror… thank you @cincytennis.” View this post on Instagram Instagram PostUp next, Coco Gauff is scheduled to return to action at the US Open. With a new coach in her corner, it remains to be seen if the American can lift her second Grand Slam trophy of the year.