Lewis Hamilton recovered from an early track breakdown to post the fastest time on the opening day of the two-day Test in Bahrain.
Toto Wolff claims Mercedes don't like favouring one driver over another but "the situation is different now" as Ferrari win again.
Lewis Hamilton admitted he felt "deflated" after a five-second time penalty cost him the chance of victory in the Bahrain GP.
Sebastian Vettel claimed victory at the Bahrain Grand Prix after title rival Lewis Hamilton was hit with a costly race penalty.
Have your say on Lewis Hamilton's race-costing five-second penalty in the Bahrain GP.
Lewis Hamilton doesn't expect Mercedes to be able to maintain their qualifying superiority over Ferrari on race day in Bahrain.
Mercedes have admitted Lewis Hamilton-Valtteri Bottas as team-mates does not have the same "stress" as Hamilton-Rosberg.
Lewis Hamilton is braced for a "great battle" in Bahrain after Ferrari topped practice and Red Bull also ran the top two close.
Lewis Hamilton wants McLaren to appoint Jenson Button as Fernando Alonso's replacement for the Monaco GP.
Lewis Hamilton has described his clash with Sebastian Vettel for the F1 2017 Drivers' Championship as the 'ultimate fight' he has faced in Formula 1.
Lewis Hamilton may have won the Chinese GP but the lap charts suggest Sebastian Vettel was right to claim Ferrari were fastest.
Lewis Hamilton is braced for the "closest fight" of his F1 career after drawing level on points with Sebastian Vettel.
Chinese GP pole-sitter Lewis Hamilton says he is relishing the challenge of "real racing" against a resurgent Sebastian Vettel and Ferrari in Shanghai.
Lewis Hamilton would welcome being reunited with Fernando Alonso as team-mates, according to Sky F1's Johnny Herbert.
Lewis Hamilton took to the track just twice on Friday's abandoned day of China practice - once in his Mercedes and once on foot!
Lewis Hamilton is optimistic the close Mercedes-Ferrari battle from Australia sets up F1 2017 for a season of "exciting racing".
Lewis Hamilton is at the peak of his powers as a Mercedes driver, according to his team boss Toto Wolff.
Lewis Hamilton has poured cold water on suggestions Fernando Alonso could join him at Mercedes in 2018.
Is F1 finally set to produce the first Lewis Hamilton v Sebastian Vettel title duel after the pair battled in the Australian GP?
Mercedes have explained their "very difficult" strategy dilemma in the Australian GP after being defeated by Ferrari.
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