World No.11 Sloane Stephens announced on social media that she and coach Sven Groeneveld have ended their professional partnership.

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"After much thought, [Groeneveld and] I have decided to go our separate ways," Stephens stated on Twitter. "Change is never easy, but I’m so appreciative of our time together. Onward!"

The former World No.3 made the announcement one week before the year's final Grand Slam, the US Open, kicks off on Monday. Stephens won her only major title to date at the US Open two years ago.

Stephens and Groeneveld linked up in early May of this year, as the American had split with her previous coach Kamau Murray at the end of last season. In their first event together since the announcement, Stephens had a strong result, reaching the Madrid semi-finals before losing to eventual champion Kiki Bertens.

Stephens then fell in the quarter-finals at Roland Garros as the reigning runner-up. She is 1-3 during the American hardcourt swing, losing in the third round of Cincinnati to eventual finalist Svetlana Kuznetsova, and dropping opening round matches in Washington (to Rebecca Peterson) and Toronto (to Marie Bouzkova).

Groeneveld had a long-term coaching partnership with former World No.1 Maria Sharapova, and the Russian claimed the 2014 French Open title under his watch. Groeneveld and Sharapova worked together until March of 2018.

Groeneveld has also worked with Monica Seles, Arantxa Sánchez Vicario, Mary Pierce, Caroline Wozniacki, and Ana Ivanovic. He coached Ivanovic during 2008, when the Serb won the French Open and ascended to World No.1.