World champion Lewis Hamilton started his bid for a fifth drivers' championship in ominous fashion by topping the time sheets in both practice sessions for Sunday's Australian Grand Prix. The Mercedes-GP driver set a fastest time of 1 minute, 23.931 seconds around Melbourne's Albert Park to set himself as the favourite to take pole position in Saturday's qualifying session. <strong>____________</strong> <strong>Read more</strong> <strong><a href="https://www.thenational.ae/sport/f1/lewis-hamilton-vows-to-work-harder-than-i-have-ever-worked-before-as-he-chases-fifth-formula-one-world-title-1.712998">Lewis Hamilton says he will work 'harder than I have ever worked before'</a></strong> <strong>Formula One 2018 calendar: <a href="https://www.thenational.ae/sport/f1/formula-one-2018-calendar-race-dates-in-uae-time-as-lewis-hamilton-bids-for-fifth-world-title-1.702709">Race dates - all in UAE time</a></strong> <strong>___________</strong> The Briton has taken pole the past four years in Melbourne, but fears of Mercedes domination after pre-season testing were relaxed a little by the strong pace of the Red Bull Racing car of Max Verstappen, who was only a tenth off a second off Hamilton on 1.24.058. Hamilton's teammate Valtteri Bottas was third fastest, with the Ferraris of Kimi Raikkonen and Sebastian Vettel fourth and fifth quickest, ahead of the Haas of Romain Grosjean. Australian Daniel Ricciardo was only seventh quickest in the second Red Bull, while the McLarens of Fernando Alonso and Stoffel Vandoorne belied a trouble winter's testing by being eighth and 10th fastest. Qualifying starts at 10am UAE on Saturday with the race beginning at 9.10am on Sunday.