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Andretti Autosport driver Ryan Hunter-Reay will go into qualifying for the GoPro Grand Prix of Sonoma with the fastest practice time of anyone following two 45-minute sessions on Saturday
Hunter-Reay, whose dwindling championship hopes took a knock last weekend with an early retirement at the Milwaukee Mile, laid down an early declaration of intent in the first session in the morning with a lap of 110.481mph (1:17.7150s) on the 2.385-mile, 12-turn road course in Sears Point, California.
That put him 0.1840s clear of second-place man Scott Dixon, whose Ganassi team mate Tony Kanaan was also in form in third place just under three tenths further back.
However the leading contenders for the 2014 Verizon IndyCar Series title, Penske team mates Helio Castroneves and Will Power, were also looking strong in fourth and fifth places. Power has won here on three previous occasions in 2010, 2011 and 2013 and another victory this weekend would give him a welcome margin of comfort going into next week's season finale at Auto Club Speedway, Fontana.
The afternoon session saw times slower than they had been in the morning. Castroneves was fastest in the session with a time of 109.156mph (1:18.6582s) just 0.0338s ahead of the third Ganassi driver Ryan Briscoe, while Hunter-Reay was in third place ahead of Dixon and Power.
Only Dale Coyne Racing's Carlos Huertas improved his time in the afternoon; however he was still 21st on the timesheets for the session just ahead of Jack Hawksworth, and overall was still the slowest man of the day and 2.1248s off Hunter-Reay's benchmark.
There were no full course cautions during either of the practice sessions on Saturday, although several cars ended up making off-road excursions into the dust and dirt run-off areas. Power, Castroneves and Mike Conway were among those exploring the limits in the morning session, while James Hinchcliffe managed spins at both hairpins early in the afternoon session.
However it appeared to be Simon Pagenaud with the most problems, going off track in both of the practice sessions with what Schmidt Peterson Hamilton Motorsport team manager Rob Edwards described as "a braking issue". Despite the recurring problem, the Frenchman - who is currently in third place in the championship just behind the Penske pair - was able to post the 16th fastest time in the morning and overall, and was 13th fastest in the afternoon session.
Heading into qualifying, teams using Chevrolet engines appear to have the whip hand at Sonoma, with Hunter-Reay the only Honda-powered car in the top six practice times. In total, eight of the top 12 times were set using Chevy units.
Earlier in the day, the engine manufacturer had confirmed that it had already clinched victory in the manufacturer's championship over Honda for the third successive year since returning to the IndyCar Series as a supplier.
"If you peel back the competition, there are two manufacturers with excellent teams that are working hard to outsmart and beat the other," said Derrick Walker, IndyCar's president of competition and operations. "It's one of the most competitive championships in motorsports with two seriously-competitive and equally-matched companies. It is one of our crown jewels of competition within the competition."
Qualifying takes place at 4.35pm Pacific Standard Time (12.35am BST on Sunday morning) and follows the familiar street/road course elimination round format in which the field is split into two groups of 11 and given ten minutes on track to set their best times. The top six from each group go through to round two which gets another ten minutes to select the top six cars to progress to the Firestone Fast Six pole shoot-out that sets the front three rows of the grid for the race.
On Sunday there is one final half-hour warm-up practice at 10am (6pm local time) ahead of the race itself which is due to get the green flag at 1.40pm (9.40pm BST). In the UK, the GoPro Grand Prix of Sonoma will be shown live on the digital and cable subscription channel ESPN
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