Madison Keys has ended her coaching relationship with Thomas Hogstedt. Keys’ agent Max Eisenbud confirmed the split to WTA Insider. No new coach has been announced.

The news comes on the heels of Keys’ career-best season, which saw her qualify for her first BNP Paribas WTA Finals Singapore presented by SC Global and finish the year ranked No.8.

“Thomas and I have a rich history of working together with Li Na, Maria Sharapova and most recently Madison,” Eisenbud told WTA Insider. “His work with all three of these girls speaks for itself. Coaching on the women’s tour is not easy and sometimes these relationships just don’t work out, nothing more than that.”

Keys and Hogstedt, who also coached Caroline Wozniacki and Eugenie Bouchard, began working together in April and their collaboration netted immediate results. Keys made the biggest final of her career at the Italian Open in Rome and won her second career title at the Aegon Classic in Birmingham, England, launching her into the Top 10.

Their success continued over the summer hardcourt season, as Keys made another big final at the Rogers Cup in Montréal and the semifinals at the Olympic tennis event, before making the second week at her sixth straight Slam at the US Open.

Keys is currently scheduled to begin her season in Melbourne at the Australian Open.

News of the split follows two other high-profile coaching changes, as US Open finalist and World No.6 Karolina Pliskova ended her long-time work with Jiri Vanek and No.14 Elina Svitolina ended her partnership with Iain Hughes.