Australian Open 2012: day four – in pictures

Andy Murray came up against Edouard Roger-Vasselin but the Frenchman was brushed aside by the No4 seed as Murray triumphed in straight sets 6-1, 6-4, 6-4 Photograph: Jason O'Brien/Action Images

Murray's opponent in the next round will be another Frenchman, Michael Llodra, who beat Alex Bogomolov Jr. 6-1, 6-3, 4-6, 5-7, 6-4 Photograph: Findlay Kember/AFP/Getty Images

An emphatic display from the former world No1 Ana Ivanovic sees off Michaella Krajicek in straight sets 6-2 6-3 Photograph: Jason O'Brien/Action Images

Serena Williams hits a volley during her 6-0, 6-4 victory over Barbora Zahlavova Strycova. The former champion dominated the rallies but was still pushed quite hard by the Czech player and the scoreline perhaps flattered the American Photograph: Nicolas Asfouri/AFP/Getty Images

Andy Roddick took the first set in the battle of grimacing old stagers against Lleyton Hewitt but the Australian soon had him running around. Hewitt was leading 3-6, 6-3, 6-4 when Roddick reitired through injury Photograph: Quinn Rooney/Getty Images

Novak Djokovic watches the ball drop over the net during his victory over Santiago Giraldo. The reigning champion was untroubled during his 6-3, 6-2, 6-1 win Photograph: Joe Castro/EPA

Maria Sharapova made swift progress into the third round, dropping just one game against Jamie Hampton of the US. The Russian, seeded fourth, was pushed harder than the 6-0 6-1 scoreline suggests, but the outcome was never in doubt Photograph: Jason O'Brien/Action Images

Jo-Wilfried Tsonga's power helped him in his 7-5 6-4 6-4 victory over Ricardo Mello Photograph: Mark Dadswell/Getty Images

David Ferrer concentrates hard during his 6-7, 6-2, 3-6, 6-2, 6-3 victory over Ryan Sweeting Photograph: William West/AFP/Getty Images

Gaël Monfils lost the first set to Thomaz Bellucci but came back to triumph 2-6, 6-0, 6-4, 6-2 Photograph: Mark Blinch/Reuters

Svetlana Kuznetsova's 7-6, 7-5 victory over the unseeded Sloane Stephens was probably more painful than the eighteenth seed had envisaged Photograph: Ahmad Yusni/EPA

Ninth seed Janko Tipsarevic overcame losing the first set to see off Australian wild card James Duckworth 3-6 6-2 7-6, 6-4 Photograph: Mark Blinch/Reuters

A five-setter is the last thing that Kei Nishikori or any player needs in the Melbourne heat but he remained cool enough to see off Matthew Ebden 3-6, 1-6, 6-4, 6-1, 6-1 Photograph: Andrew Brownbill/AP

Petra Kvitova focuses on the ball in order to play a backhand to Carla Suárez Navarro. The concentration paid off as she won the match 6-2, 2-6, 6-4 Photograph: Lucas Dawson/Getty Images

Philipp Petzschner doesn't think much of his own performance during his 6-7, 6-2, 3-6, 6-2, 6-3 defeat to Milos Raonic Photograph: William West/AFP/Getty Images

Sabine Lisicki powered into the third round with a 6-1, 6-2 victory over Shahar Peer Photograph: Mast Irham/EPA

Vania King slams a forehand return during her 5-7, 6-3, 6-4 victory over Anastasia Pavlyuchenkovain Photograph: William West/AFP/Getty Images