Former No. 1 Karolina Pliskova fires coach David Kotyza

FILE - In this file photo dated Monday, Sept. 4, 2017, Karolina Pliskova, of the Czech Republic, reacts after beating Jennifer Brady, of the United States, during the fourth round of the U.S. Open tennis tournament in New York. Former world No. 1 Karolina Pliskova said Friday Sept. 15, 2017, that she has parted with coach David Kotyza. (AP Photo/Peter Morgan, FILE)

PRAGUE (AP) Former world No. 1 Karolina Pliskova says she’s parted with coach David Kotyza.

Pliskova hired Kotyza, the former coach of her fellow Czech Petra Kvitova, in December.

With Kotyza, Pliskova won three WTA tournaments. She reached the semifinals at the French Open and lost in the quarterfinals of the U.S. Open to lose her No. 1 ranking.

In a message to local media on Friday, the fourth-ranked Pliskova says she and the coach failed to agree on ”the strategy of my further development.”

It is not immediately clear who will replace Kotyza.