Bianca Andreescu has made the sad decision to split with long-time coach Sylvain Bruneau, a week after losing in the first round of the French Open.
The World No.7 announced the shock news on Twitter on Tuesday.
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"It is with a heavy heart that I would like to inform my fans that my long time coach, mentor and friend, Sylvain and I, have mutually decided to end our incredible coaching relationship," she wrote.
"Our friendship will live forever ... I am very grateful for everything we accomplished together and all of our great memories.
"Sylvain was more than a coach... he is family."
Andreescu and Bruneau had worked together for four years as the Canadian made her breakthrough in 2019 with three titles.
That included her maiden grand slam triumph at the US Open when she famously beat Serena Williams in the final.
The 20-year-old returned to action at this year's Australian Open having missed 15 months due to a number of injuries.
A positive COVID-19 test then ruled her out of the Madrid and Rome Opens before an abdominal injury forced her to pull out of Strasbourg at the quarter-final stage.
Her most recent appearance at Roland Garros ended with a 6-7(1) 7-6(2) 9-7 loss to Tamara Zidansek, who has since become the first Slovenian woman to reach the semi-finals of a grand slam.
Zidansek and Pavlyuchenkova in French Open semi-final
Zidansek and Anastasia Pavlyuchenkova will ensure the French Open has a wholly unexpected singles finalist after they battled their way through roller-coaster last-four examinations at Roland Garros on Tuesday.
World No.85 Zidansek said she "fought for her life" to overcome Spain's 33rd seed Paula Badosa 7-5 4-6 8-6 in two hours 26 minutes.
Pavlyuchenkova, who'd previously reached six grand slam quarter-finals but never a semi, then outlasted doubles partner Elena Rybakina in an even longer, more compelling marathon 6-7 (2-7) 6-2 9-7.
The Russian 31st seed admitted it was "mentally really hard" to beat the woman she'll be partnering in Wednesday's doubles quarter-finals as she looks forward to next facing Zidansek in Thursday's semi-finals.
"It feels overwhelming, sounds crazy," smiled Zidansek, asked how it felt to be in the last-four, having never been beyond the second round.
She will now face Pavlyuchenkova, 10 years after the Russian first reached the quarters at Roland Garros as one of the rising stars of the circuit.
"I knew what to expect from her. The only thing you can do is hang in there," said Pavlyuchenkova of her win over Rybakina.
"I believed in my chances. I know I'm a fighter, so I will fight till the end. That's what I did."
Wednesday's other quarter-finals also feature some unlikely faces with Greek No.17 seed Maria Sakkari facing defending champ Iga Swiatek, while Czech doubles specialist Barbora Krejcikova faces US teen sensation Coco Gauff.
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