Kiefer, Davydenko, Grosjean all through

Nicolas Kiefer, Nikolay Davydenko and Sebastien Grosjean all booked spots in the quarter-finals after a day of tough encounters at the Australian Open.

Both Kiefer and Grosjean managed to save important energy reserves with straight-set victories, while Davydenko battled through five sets to edge out Dominik Hrbaty in a gruelling match.