Following a slew of shocking losses in her last few tournaments, Agnieszka Radwanska has announced her split with tennis legend Martina Navratilova.

The partnership began at the start of the 2015 season but it appears that the Polish No. 1’s recent trend of frustrating losses, coupled with Navratilova’s inability to commit full-time to the job, made the split an all-too-real option for Radwanska.

“I just wanted to thank Martina for her time and efforts over these last few months,” Radwanska wrote on twitter. “It was a great experience to work with one of the all time greats. However, we both agreed that as Martina could not commit 100% to the project then it was not going to work as a long-term partnership. We will stay friends and I wish her all the best in her personal and professional life.”

Navratilova’s partnership with Aga was the latest in a long line in star coaching roles over the past few years; Andy Murray sparked the trend when he hired Ivan Lendl then Amelie Mauresmo; Novak Djokovic brought Boris Becker on board; Marin Cilic partnered with Goran Ivanisevic to win his maiden Grand Slam title; Roger Federer teamed up with his idol Stefan Edberg, while Kei Nishikori joined forces with Michael Chang.

Navratilova won 167 WTA titles over the span of her illustrious career, 18 of which were Grand Slam singles titles and won her last Grand Slam mixed doubles title at the US Open in 2006. Her rivalry with Chris Evert goes down as one of the biggest rivalries in women’s tennis, having played each other a total of 80 times, with Navratilova leading the series 43-37.