MONTMELO, Spain (AP) -- For the second time in two days, defending Formula One champion Sebastian Vettel had to walk away from his malfunctioning Red Bull and watch Lewis Hamilton speed by in his Mercedes at the Spanish Grand Prix.
Hamilton blazed to his fourth pole position in five races this season on Saturday after a faulty transmission left Vettel without power in his RB10 with just under 10 minutes to go in qualifying.
Vettel will now start Sunday's race at the Barcelona-Catalunya circuit from a distant 15th place.
The four-time champion appeared to be running well through the early practice session and the first two periods of qualifying, but he was soon in trouble when his car stuttered coming out of the pit lane before finally giving up on the third curve.
"I left the garage ... and lost drive in the second gear," Vettel said. "I still had third gear and above so we thought we could do the lap with that, but by turn one I had lost all the other gears, so we couldn't continue.
"I'm of course quite disappointed. These things happen, but now I just have to do the best I can from the position I am in."
Having made it into the third qualifying period, Vettel had at least secured a 10th-place start. But Red Bull later found it had to replace his car's gearbox, incurring Vettel a five-place penalty for breaking the rule that gearboxes must last six consecutive races.
This latest setback came after Vettel was stranded just four laps into Friday's practice due to a short in the car's electrical system. Hamilton also set the best times in both practice sessions on Friday.
Vettel's new teammate Daniel Ricciardo fared much better, qualifying third behind the Mercedes pair.
While Vettel continued to falter, Hamilton was poised for a fourth straight win. Teammate Nico Rosberg will start from second place looking to protect his four-point lead over Hamilton in the standings.
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