An annoyed Daniil Medvedev lost his cool in the heat of a tetchy four-set battle with big-serving American Maxime Cressy to reach the quarter-finals at the Australian Open on Monday. 

The Russian second seed took a medical timeout to have his lower back massaged and had some heated exchanges with the chair umpire before seeing out a 6-2, 7-6, 6-7, 7-5 win in 3hr 30min on Margaret Court Arena.