It was in August, after Wimbledon, that Rebecca Peterson started a collaboration with Swedish star trainer Thomas Högstedt, who previously coached, among others, Maria Sharapova.

The collaboration gave effect directly. During the fall, Peterson has climbed to a ranking among the top 50 in the world ranking, including her first two WTA titles in China.

Peterson, who has had injury and illness issues lately, missed the Fed Cup qualifier this weekend, has hailed the collaboration with Högstedt.

- He has meant an incredible amount. He himself has played and coached many top players and I am glad that he wants to share his experience with me. I have become better technically, tactically and mentally, she has told SVT Sport.

It is unclear why the couple is breaking their cooperation.

"We choose to go different paths," writes her father and coach Mart Peterson in a text message to Expressen.

SVT Sport has applied for both Rebecca Peterson and Thomas Högstedt without success.

REPORTAGE: SVT Sport meets Peterson in USA (January 19)

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