Will Power picked up his fourth pole position of 2012 and his third in a row at Sonoma, with a lap of 1:17.2709s (111.115mph) that was 0.1638s faster than second-place man Ryan Briscoe.

"It's good to back on the pole here in Sonoma," he said. "It is important to start up front here and we are very happy to once again be on the front row, which is where we want to start."

Last year, Penske locked out the top three positions - and then went on to finish the race in the same order. Despite changes to the Sonoma Raceway circuit designed to promote more racing action in 2012, Power is understandably hopeful that he, Briscoe and Helio Castroneves can achieve similar success this year.

"This track was great for the team and we look to continue our success as a team here," he said. "I just really like this track and I would love to make it three in a row here."

However, the team has already been thwarted in its attempt of locking out the top three spots on the grid, thanks to a superb flying lap by Sebastien Bourdais who has been strong all weekend and who will now start from third place at the green flag.

"We came a long ways, obviously, from the start of the season with all the struggles we had to go through," said Bourdais, referring to Dragon Racing's underpowered early races with Lotus engines, their acrimonious split from the British manufacturer and the need to rebuild from that low point after signing a single-engine supply deal with Chevrolet in May.

"The last few events you see have been getting better and better and the team has done a great job, and we definitely feel that we have a much better idea of what we need on the car and where we are at," said Bourdais. "We keep chipping away and finding little stuff. And one after the other, you get closer to these guys. It's not easy. I think everybody, most everybody in the field feels like the guys at Penske have got it all figured out, and they've been dominating all weekend so far."

Bourdais' job on Sunday afternoon will be to keep his car in front of Castroneves, who will be looking to make an early jump to join his team mates in the top three. The Brazilian was hopeful that he could do just that on race day.

"We found some stuff in the car,," he revealed. "We did find something. I'm not allowed to disclose what it was, but certainly improved my end. I'm still far away from my teammates, certainly they did a great job. So obviously better than yesterday, but I'm not happy compared to what my guys have."

Even so, Helio still looked happier than the Ganassi duo of Scott Dixon and Dario Franchitti, who made it through to the final Firestone Fast Six round of qualifying but ended up having to settle for occupying the third row of the grid side-by-side for the start of Sunday's GroPro Indy Grand Prix.

"It's good to be in the Firestone Fast Six with as competitive as the series is now, but this is not the end of the Firestone Fast Six you want to be in," admitted Franchitti. "We'll try to make some stuff happen tomorrow."

"It was okay," shrugged Dixon. "I'm happy with the balance. The balance of the car is good. I think we're just lacking grip. If you look at turn 7 and 9 we're missing quite a bit of speed there in those sections. Some of that might be me. We're missing like a half a tenth to a tenth throughout the whole track which is a bit frustrating."

The first group in round 1 was even more sluggish getting underway than usual, with James Hinchcliffe the first car out after half the 15 minute session had already expired. By the time the chequered flag dropped on the session, Ryan Briscoe topped the timesheets with a lap of 1:17.5515s (110.713mph) half a second clear of Dario Franchitti. Helio Castroneves, Sebastien Bourdais and Justin Wilson also made it through, and Hinchcliffe himself squeaked into round 2 by just 0.0249 over Sebastian Saavedra. The biggest name to fall at the first hurdle was Graham Rahal, who ended the session six hundredths of a second behind Saavedra in eighth.

"We're disappointed in today's qualifying run," said Rahal after his early exit. "We were bumped out by a slim margin but that's all it takes. We had a really strong weekend and then it comes down to qualifying and we just didn't have enough. We just have to go back and figure out what's going on."

The second group was slightly quicker to get underway, with Mike Conway and James Jakes first to get out on track; however, neither driver made it through to the next round. Predictably, Will Power topped the session with a lap of 1:17.7803s (110.388mph) over six tenths clear of Ryan Hunter-Reay. Also progressing from the round were Simon Pagenaud, Alex Tagliani and Scott Dixon, with Rubens Barrichello securing the final berth in round 2 by edging out Marco Andretti. Oriol Servia failed to progress, and Tony Kanaan was another surprise early exit.

"I had a solid first timed lap and the car felt good," explained Kanaan. "On my next lap I was running three tenths of a second faster, but I got blocked going into turn four. That pretty much ended any chance of getting into the second round of qualifying."

Round 2 comprehensively confirmed Penske's form at Sonoma for the second year running, although for once Power had to settle for second best to his team mate Ryan Briscoe whose lap of 1:17.5378s (110.733mph) was 0.0453s faster than the championship leader could manage. Sebastian Bourdais was the fastest non-Penske runner in third, pushing Dixon down to fourth ahead of the final member of the Penske squad, Helio Castroneves. Dario Franchitti made it into the top six by the skin of his teeth just 0.0169 ahead of Ryan Hunter-Reay, who will be the highest-placed of the Andretti Autosport drivers at a circuit that they admit they struggle at.

"Historically this has not been one of our best tracks, and considering how we struggled yesterday, we shouldn't be bummed by seventh," said Hunter-Reay as he climbed out of the #28.

"Two of our wins came when we qualified seventh, so we know we can do it from there, but it's still frustrating to miss the Fast Six," he continued. "We had five laps of fuel in the car, but we had trouble with the starter on pit lane, so that meant we only had time for four laps in that session. We missed sixth by a few hundredths, so that fuel level would have made the difference in the lap time."

Also missing out on progressing were road course specialists Simon Pagenaud and Rubens Barrichello.

"We just don't have it," admitted the Frenchman. "I think we may be missing grip in a few places because, overall, my balance is really good. I think I got the most out of the car but not the most out of the tyres. We just don't have as much grip as the Penske cars and a few others. We need to find a little bit more."

"I was happy that we made it through to the second round of qualifying," contributed Barrichello, who will start the race from just outside the top ten. "We made an adjustment after the first round, but the car was still on the limit. Hopefully, with a good strategy tomorrow I will be looking at a top-five finish."

That second round set the broad pattern for the Firestone Fast Six which decided the first three rows of the grid, although Power once again flexed his muscles and propelled himself back on top ahead of Briscoe with a lap of 1:17.2709s (111.115mph) which was 0.1638s faster than his team mate, who will start alongside him on the front row for tomorrow's race. It's Power's 28th pole of his IZOD IndyCar Series career.

Sebastien Bourdais managed to stop a repeat of 2011's Penske top three lockout on the grid by firmly eclipsing Helio Castroneves for third place by more than three tenths. The Ganassi duo of Scott Dixon and Dario Franchitti had to settle for sharing the third row of the grid, and face a reprise of the same gloomy scenario they endured last year when the top five drivers all finished in the same position in which they started. Despite the recent tweaks of the Sonoma circuit intended to aid overtaking and improve the racing action for fans, there's still every possibility that Penske will again emerge with a top three lockout in the race itself if they can dispatch Bourdais early in the day.

Power remains cautious about his chances of success, however. "The wind really made the car unstable the last two days, so it will be interesting to see what the wind is like tomorrow," he pointed out. "And it will also be interesting because the race is an extra ten laps."

There were no red flags during any of the rounds of qualifying, but Sebastian Saavedra had his fastest lap deleted in round 1 for a pit lane entry violation. Saavedra is also one of four who will have ten-place grid penalties for the start of tomorrow's race for unapproved engine changes: the others are Takuma Sato, Justin Wilson and Simona de Silvestro.

Full qualifying times are available.