McLaren's Lewis Hamilton lost his pole position for Sunday's Spanish Grand Prix after Formula One's governing body, the FIA, determine his car did not have sufficient fuel on board during qualifying.
Pastor Maldonado from Williams surprisingly held the provisional pole in the closing minutes of Q3, but Hamilton turned a fast lap around the 4.655- kilometer (2.892-mile) Circuit de Catalunya in 1 minute, 21.707 seconds to claim 22nd career F1 pole.
Hamilton's time was 0.578 seconds quicker than Maldonado's lap. Hamilton came to a stop on the track at the end of Q3 after being told on his team radio to pull over. McLaren determined there wasn't enough fuel in his car to enable it to return under its own power to pit road.
"I stopped on the track, because I was told to stop," Hamilton said during a post-qualifying news conference. "I don't have any idea why. The car was feeling great today."
Per FIA's technical regulations, McLaren had to provide a one-liter fuel sample in post-qualifying scrutineering. The team argued the insufficient fuel was due to reasons of "force majeure," since a crew member put an inadequate amount of fuel into the car.
After a lengthy discussion, race stewards rejected McLaren's case and excluded Hamilton from Saturday's qualifying results. Therefore, the Briton will start last in the Spanish GP.
The FIA explained in a statement, "A team member had put an insufficient quantity of fuel into the car, thereby resulting in the car having to be stopped on the circuit in order to be able to provide the required amount for sampling purposes. As the amount of fuel put into the car is under the complete control of the competitor, the stewards cannot accept this as a case of 'force majeure'.
"The stewards determine that this is a breach of Article 6.6.2 of the FIA Formula One Technical Regulations, and the competitor is accordingly excluded from the results of the qualifying session. The competitor is however allowed to start the race from the back of the grid."
Maldonado will start on the pole for the first time in his early F1 career.
"We've been working so hard since the beginning of the year trying to understand these tires and to develop our car around the tires," Maldonado said. "We had a very good step forward for this race."
Spaniard Fernando Alonso will start second in front of his home crowd. The Ferrari driver posted a lap in 1:22.302.
Ferrari dealt with performance and reliability problems with its cars when F1 held pre-season testing at this circuit two months ago. Alonso had qualified no better than eighth in the first four grand prix this year.
"For us, it was impossible to dream about being in the top three in the first four races," he said. "It's definitely a step forward."
Lotus teammates Romain Grosjean and Kimi Raikkonen start third and fourth, respectively. Sergio Perez from Sauber rolls off fifth and Nico Rosberg sixth.
Two-time defending world champion and current points leader Sebastian Vettel finished eighth in qualifying after his Red Bull team opted not to make a qualifying run during Q3.
"We decided to abort the lap to have a free choice of tires for the race," said Vettel, who now starts seventh. "If I had set a lap, we would have to start the race on soft tires."
Michael Schumacher from Mercedes and Sauber's Kamui Kobayashi made it into Q3 but joined Vettel in not participating in the final segment.
Hamilton's teammate, Jenson Button, and Mark Webber, who is paired with Vettel at Red Bull, shockingly failed to advance into Q3. Button experienced balancing issues with his car during Q1 and Q2.
"I don't know where it went wrong," Button said. "I've struggled with balance all day. We were quickest on the soft tire yesterday. I thought we would be reasonably competitive and at least get into Q3, but that's not the case."
Webber turned a lap early in Q2 but did not make another lap for the remainder of the session to save his tires. He started on the pole for last year's Spanish GP.
"The first lap in Q2 was very competitive, but it lulled us into a false sense of security, so we parked up the car," said Webber, who will start 12th.
Vettel, who won the most recent grand prix in Bahrain three weeks ago, holds a four-point lead over Hamilton in the championship standings. Webber is five points behind his teammate, while Button and Alonso are both 10 markers out of the lead.
The 66-lap Spanish GP is scheduled to start at 8 a.m. (ET).