Scott Dixon's bid for a fourth straight victory on the road course at Watkins Glen, N.Y., ended Sunday with an uncharacteristic mistake that gave Ryan Hunter-Reay the opening he needed to earn his first IndyCar Series victory.

Dixon, preparing to make a run at leader Darren Manning after a long caution period, spun out under yellow and was hit from behind by contender Ryan Briscoe. That gave the runner-up spot to Hunter-Reay, who easily passed Manning on the restart and drove away with the fourth series win for Rahal Letterman Racing.

It is the third open-wheel victory for Hunter-Reay, a Texas-born driver who won twice while driving in the now-defunct Champ Car World Series.

"It's huge," Hunter-Reay said after doing some celebratory burnouts. "I'm an American boy ... and this is a real Fourth of July weekend celebration."

It was a strange finish to a race that went the first 40 laps on the 3.4-mile, 11-turn circuit with only a couple of minor incidents and wound up running under caution for most of the last 20 laps because of a series of crashes and spinouts.

Dixon, trying to become the first IndyCar driver to win four straight races on any track, appeared to be in position, with only the vulnerable Manning ahead of him as the field was about to get the green flag with 12 laps remaining.

The series leader, winner of two races this season, including the Indianapolis 500, said he was trying to get some heat into his new front tires after pitting on Lap 41. He shot forward and, suddenly, his Chip Ganassi Racing Dallara spun out of control.

ALSO SUNDAY

BRITISH GRAND PRIX: Lewis Hamilton mastered wild and wet racing conditions to score a runaway victory at Silverstone, England, and throw the Formula One championship wide open.

After he failed to collect a single point from the previous two races in Canada and France, Hamilton's title hopes would have been in trouble if the same had happened in front of his home fans.

But the 23-year-old British driver, who last year squandered a 12-point lead with two races left in his rookie season, stayed in control on a rain-soaked track that plagued his rivals. Many were unsure which tires to use and repeatedly spun or veered off the circuit.

Hamilton led from the fourth lap in his McLaren to win his first British GP and take the lead in the standings.

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