Emma Raducanu has "put herself in a difficult position," by chopping and changing coaches so much, according to John McEnroe.
Raducanu had a stunning breakthrough at the US Open last year as she became the first qualifier to ever win a major.
Her progress has significantly stalled since, and she crashed out of the French Open in the second round on Wednesday.
McEnroe, though, believes she is creating problems for herself by going through four coaches in a year before ultimately deciding to carry on without one at all.
"She has changed coaches three, four or five times which is unbelievable for someone who has just come off winning a major," McEnroe told Eurosport of Raducanu.
"I think movement is an issue for her, obviously experience, she is still very young.
"She has sort of put herself in a difficult position because a lot is expected of her and with the people around her, we are not sure if she is comfortable with them just yet. Hopefully in the next year or two she will find that.
"Honestly, if I won the US Open having gone through qualifying, I wouldn't have changed my coach at least for the next year, so I don't understand that move.
"Obviously her parents are involved and they know more than I know. But this idea of a revolving door of coaches I just don't think that's good for any player, much less so for a player at this stage of her career.
"We have to wait and see and hopefully she finds someone she can stick with for a while."