Jenson Button suffers electrical shutdown in FP1 and a control data issues in FP2.
Vettel suffered front wing damage after hitting Mexican on the inside of Turn 1.
Alonso finished 7th and 12th in two Friday sessions in Bahrain as McLaren continues slow and steady progress.
World champion says Mercedes' one-lap pace meant they could put main attention on perfecting race pace on Friday in Bahrain.
Rosberg thinks Ferrari will be a genuine threat for the victory on Sunday, even though Mercedes has maintained one-lap advantage.
German pips Lewis Hamilton to P1 as Mercedes shows it has still maintained one-lap advantage over Ferrari.
Says finishing position is still second priority as McLaren looks to continue making progress, but thinks a place in Q2 is possible in Bahrain.
Nico Rosberg says 'It was very important [to beat Hamilton] already in Malaysia, so that doesn't change.'
Can Ferrari continue to push Mercedes or will the Germany team run away with the championship?
Will engine updates in Bahrain and Spain see further movements up the grid for Jenson Button and Fernando Alonso?
ESPN F1 deputy editor Laurence Edmondson looks ahead to a night race in Bahrain as Lewis Hamilton and Nico Rosberg hope to extend their lead at the top.
World champion says he has spoken to Nico Rosberg and insists there is "no issue" lingering between the Mercedes drivers since the Chinese Grand Prix.
Kate Walker looks at a landmark disclaimer on F1's official website and what impact it could have on host nations like Bahrain.
Mercedes boss insists team did everything to ensure nothing 'carried over' to Bahrain Grand Prix between Nico Rosberg and Lewis Hamilton.
The latest betting tips from the ESPN team, in association with bet365
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