Prague - Two-time Wimbledon champion Petra Kvitova has hired Karolina Pliskova's former coach - and Pliskova has hired Kvitova's former coach.
The 11th-ranked Kvitova will now work with Jiri Vanek, who parted ways with Pliskova last month.
The sixth-ranked Pliskova, meanwhile, has hired David Kotyza, whose seven-year partnership with Kvitova ended in January.
With Vanek, who joined her in 2014, Pliskova jumped into the top 10 and reached the US Open final.
During her seven years with Kotyza, Kvitova won 17 WTA titles, including Wimbledon in 2011 and 2014.
But she struggled after their split, and former doubles specialist Frantisek Cermak, who was coaching her from April until September, wasn't able to turn around her fortunes.