Iga Swiatek has split from her coach Piotr Sierzputowski after working together for almost six years.
Swiatek, who won the French Open in 2020, hired Sierzputowski when she was 15-years-old in January 2016 and has since gone on to become a Grand Slam title winner and reached as high as number four in the WTA rankings.
But Swiatek says she has had to make a challenging decision to drop her coach.
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The 20-year-old wrote on Instagram: "This change is really challenging for me and this decision wasn't easy, either.
"I would like to thank you coach for everything that you did for me, we gave each other so much and I hope that we'll continue to grow and develop with this experience we've gained together.
I owe you a lot and truly appreciate the time we've spent together. All those years enabled us to be in the place that we are now.
Swiatek was knocked out of the 2021 French Open at the quarter-final stage and lost in the fourth round at the Australian Open, Wimbledon and the US Open.
The Pole finished the year ninth in the rankings and with two WTA titles. She has not said who her next coach will be.
She continued: "As tennis players we meet on our path a lot of people who contribute great value into our work and, often, into our life too, because we spend almost the whole year on tour together.
"I found out that sometimes in our professional life we need changes to develop more, evolve and meet other people with whom we're going to create a cooperation for the next stages of our development."

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