Emma Raducanu has been urged to slow down the churn of coaches by her side as Russian Dmitry Tursunov claimed he walked away from the British player because of "red flags".
Tursunov, a former top-20 player and seven-time title winner on the men's tour, said Raducanu needs to listen to "one voice" and see where that takes her, after he became the latest coach to part ways with the former US Open winner.
It emerged in early October that Tursunov had called a halt to working with Raducanu, and he has taken up a role with Swiss player Belinda Bencic instead.
Tursunov told tennismajors.com how "emotionally" he had wanted his trial period with Raducanu to become permanent, insisting he saw rich potential in the 19-year-old, but he suspected there would "be problems later".
Former Davis Cup winner Tursunov did not specify who or what he saw as being a stumbling block to working with Raducanu on a permanent basis.
"I was walking away from Emma regardless of whether there was another [player] available or not," Tursunov said. "We didn't agree on the terms and there were some red flags that just couldn't be ignored."
Raducanu turns 20 in November. As well as Tursunov, in the past 18 months she has worked with Nigel Sears, Andrew Richardson, Torben Beltz and the Lawn Tennis Association's Iain Bates.
Her growing list of former coaches is notable and the focus on that factor could influence those Raducanu wishes to work with in the future.
Tursunov said Raducanu was "minimum a one-year project but... probably a two-and-a-half-year project to be on the safe side", and reasoned that her game remained "very raw".
"It’s going to take some time, but as I said to her and to pretty much everyone on her team: I think you just need to have one voice and just try that for a bit," Tursunov said
He said he "stuck around" after a trial around the US Open and was looking for assurance that, if taken on, he would be given time to work towards long-term goals.
"But of course, with her coaching situation, there's now a thought going through every coach's mind," Tursunov added.
Raducanu has not reached a final since her dazzling Flushing Meadows victory, but Tursunov has no doubt about the talent of a player he describes as "absolutely great" and "hungry to improve".
There have been just four quarter-final runs in the wake of her September 2021 triumph in New York, with Raducanu only converting one into a semi-final appearance
Tursunov, 39, says Raducanu "has a tremendous upside", but he also issued a warning, adding: "The ingredients are very good, but you can still mess it up."