SAKHIR, Bahrain : Mercedes further demonstrated its early-season dominance by outpacing its rivals in Friday's practice sessions for the Bahrain Grand Prix, indicating the team is well poised for a third straight win to start 2014.
Lewis Hamilton followed up his victory last week in Malaysia by having the fastest time in both sessions, the second of which was held under lights for the first time at the Bahrain International Circuit, which has switched to being a night race.
Hamilton's time of 1 minute, 34.690 seconds was one third of a second faster than teammate and championship leader Nico Rosberg, and more than a second faster than third-place Fernando Alonso of Ferrari.
"The car feels better than when we were testing here -- balance-wise, it was extremely good," Hamilton said. "There are still some tweaks we need to make it feel perfect, but I'm feeling good."
Defending four-time world champion Sebastian Vettel was a distant seventh on the timesheets, behind his fourth-place Red Bull teammate Daniel Ricciardo -- who carries a 10-grid-place penalty into Sunday's race. The pair was split by Felipe Massa of Williams and McLaren's Jenson Button.
Vettel, who was a competitive third in Malaysia, was downbeat about Red Bull's prospects of hanging on to the Mercedes coattails on Sunday.
"They are very quick. It is not a surprise, they were very quick in the testing here. They have proved that again," Vettel said. "It will be a long way for us to catch up."
Even more dispiriting for Mercedes' rivals was that the dominance reflected by their lap times on lighter fuel and soft tires was even more pronounced when using higher fuel loads to practice for race conditions.
Williams had a distinctly different approach to the day's practice, doing relatively few laps to extend engine life, reckoning that it had all the data it needed about the Bahrain track after extensive preseason testing there.
Toro Rosso rookie Daniil Kvyat was eighth fastest, ahead of McLaren's Kevin Magnussen and Force India's Sergio Perez.
The night session, which began in falling desert temperatures at 6 p.m. local time -- the same as Sunday's race -- saw many drivers struggling to get sufficient heat in the tires, misjudging braking distances and running off track.
Max Chilton's Marussia went into a violent spin after a front brake failure, while Sauber's Adrian Sutil and Caterham's Marcus Ericsson both had sudden power losses.