Coco Gauff says she didn't hesitate to shake up her team just days before the US Open, hoping a new specialist coach can help shore up the serve that has been letting her down.

"It was a very sudden decision" to hire biomechanics expert Gavin MacMillan, Gauff acknowledged on Friday as she spoke to reporters ahead of the final Grand Slam of the year.

"Gavin became available. I just felt this was the best decision for my game at least and I had to go with what I was feeling."

She had kind parting words for former coach Matt Daly, but clearly thinks that MacMillan -- who helped world number one Aryna Sabalenka sort out a slumping serve -- has the expertise she needs.

"I'm just looking at long term," said the world number three, who won her first Grand Slam title at Flushing Meadows in 202

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