Australian Open: Kvitova, Federer, Nadal in action

MELBOURNE, Australia (AP) — Two-time Wimbledon champion Petra Kvitova opens play at Rod Laver Arena on Day 7 of the Australian Open with a match against 17-year-old American Amanda Anisimova.
Anisimova has beaten two seeded players on her way to the fourth round and a win Sunday would advance her to a quarterfinal against either Ashleigh Barty or Maria Sharapova, who meet in the following match at Rod Laver.
Rafael Nadal is to play his Round of 16 match against Tomas Berdych. Six-time cham