Coco Gauff’s surprise fourth-round exit from the women’s singles at the US Open has left many dissecting her game in the wake of the loss.

Third-seeded Gauff lost to 13th-seeded Emma Navarro in three sets, 6-3, 4-6, 6-3, with the 20-year-old making more double faults (19) than winners (14) in Sunday’s defeat.

Among those who took the opportunity to criticize Gauff was Rennae Stubbs, the former coach of 23-time Grand Slam winner Serena Williams.

Stubbs went to ESPN and discussed the matter with their tennis panel, which included Brad Gilbert, the man who currently serves as Gauff’s coach.

She openly questioned Gauff’s confidence and pointed out that her second serve was a significant “problem”.

Rennae Stubbs openly criticized Coco Gauff’s trainer Brad Gilbert after Gauff’s loss on ESPN

Gauff, the number three in singles, lost in three sets to number 13 Emma Navarro on Arthur Ashe

“Where is Coco’s confidence?” Stubbs wondered. “There’s no second serve, that’s the sign. And that’s a problem.”

Stubbs continued to criticize the 20-year-old in front of her coach – which she admitted was difficult.

“So under pressure, bad technique breaks down and her technique is… hard for me to say because Brad (Gilbert) is sitting here… but her technique, the elbow, is too low, the grip is a bit strange too.

“That’s why it’s hard for her to get that nice first serve and then the same or similar second serve,” she said.

After her loss, Gauff seemed to realize that her serve was a difficult point in the match.

When asked if she would consider hiring a biomechanics coach to advise her on her serve motion – as Aryna Sabalenka recently did with such great success – Gauff replied: “Absolutely. I definitely want to get other opinions, but I also think sometimes it’s more of an emotional, mental thing, because if I went on the practice court now, I would do about 30 serves in a row. I’ve done that before.”

“It’s kind of a mental hurdle that I have to overcome. But yeah, I definitely want to look at other things because I don’t want to lose games like that anymore.”

Gauff also praised her opponent and said of Navarro: “She is a great returner. She does a great job when it comes to redirecting the ball. She is kind of an all-round player. She can do anything.”

Fans called for Gauff to leave Gilbert, and Nick Kyrgios openly offered to step in

Fans have recently been clamoring for Gauff to split from Gilbert after a season in which she reached the semifinals at the Australian Open and Roland Garros, but was eliminated in the fourth round by Navarro at Wimbledon and the US Open.

Remarkably, she won the doubles title at the French Open with Katerina Siniakova – a highlight of a turbulent year.

A possible candidate to succeed Gilbert is Nick Kyrgios, who has openly offered to coach the 20-year-old on X (formerly Twitter).

When a user on the social media platform suggested her as a possible replacement for Gilbert, the Australian said: “I would coach her.”

Kyrgios currently works as a courtside reporter for ESPN.