Pliskova used to have biggest serve in WTA but now everybody breaks her just for fun. Her baseline game is not good enough for her to win tournaments at all
Sascha has only really had success with the players that would already have had success like Osaka, Serena & Woz. Ever since he’s started with other players it’s gone wrong, I guess you could argue he’s picking the wrong players but Pliskova has gone so downhill since the start of the year.
But Karolina was better than she is now, he's making her worse