Madison Keys has knocked Wimbledon champion Petra Kvitova out in the third round at the Australian Open, beating the fourth seed 6-4 7-5 this afternoon.

The American got an early break in the first set as she looked to put the Czech player under pressure, but Kvitova got the set back on level terms straight away.

Keys used her powerful forehand to edge in front again though, and this time was able to serve out for a one-set lead in the Rod Laver Arena.

The American continued to put Kvitova under pressure during her service games in the second set, but she was twice broken back by the two-time Grand Slam champion.

However, the fourth seed dropped her serve again at 5-5 to leave Keys serving for the match, and she delivered a series of powerful serves to comfortably wrap it up.

The 19-year-old, who has never reached the fourth round in Melbourne before, will face compatriot Madison Brengle in the next round.