The Team Penske driver finished nearly a second in front of Alexander Rossi, who also was the runner-up at the Indianapolis 500, and Takuma Sato. Newgarden, who opened the year with a victory at St. Petersburg, joins Indy 500 champion Simon Pagenaud as the series' two-time winners this season. Newgarden has won 12 IndyCar races since 2015.
Pagenaud finished sixth after starting 13th in the 22-car field on Belle Isle. The 70-lap race became a 75-minute timed event after thunderstorms delayed the start by more than an hour. There were five yellow periods due at least in part to conditions, leading to 14 laps under caution and 29 under green.
Josef Newgarden led the Detroit Grand Prix midway through the 75-minute race.
The Team Penske driver was out front when the yellow flag came out for a third time after Will Power's front left wheel was not secured during a pit stop and came loose.
Pole sitter Alexander Rossi led for the first 18 laps of the race before taking his first pit stop. Rossi was second when the race resumed followed by Scott Dixon, who later hit a wall to tire barrier to bring out another yellow flag.
The 70-lap race was shortened to a timed event because of a delay of more than an hour and with more storms swirling Saturday around the Motor City.
The Detroit Grand Prix has begun, starting under a yellow flag after Zach Veach spun out just before the race was to begin following a weather delay Saturday.
Shortly after the race began on the rain-soaked track, the yellow flag came out again because Matheus Leist briefly lost control of his car.
The 70-lap race was reduced to a 75-minute timed event. It started after a delay of more than an hour and more than 2 hours after spectators were told to take cover because of a severe thunderstorm warning.
The first of two Detroit Grand Prix races has been shortened because of a thunderstorm.
Race officials decided to turn the 70-lap race into a 75-minute timed event. Alexander Rossi will have the pole for a single-file start about an hour after the race was scheduled to begin.
The start of the Detroit Grand Prix has been delayed.
A severe thunderstorm warning led to the track and stands being cleared about 90 minutes before the start of the race.
Race officials were unable to provide estimates for a possible start time for the first of two IndyCar races.
Thunderstorms may delay the first of two Detroit Grand Prix races.
Spectators on Belle Isle were advised to exit the stands and seek shelter about 90 minutes prior to the scheduled start of the race Saturday afternoon.
The National Weather Service issued a severe thunderstorm warning that was to end just minutes before the first of two races this weekend in the Motor City was to begin.
Alexander Rossi looks like he may be the driver to beat at the Detroit Grand Prix.
Rossi started first when he went on to win four of the six races in his career. He earned the pole for of two races scheduled on Belle Isle. Severe weather in the area might push back the mid-afternoon start of the race.
Rossi hopes his next run in the Motor City goes better than his last one on the 2.35-mile road course on the banks of the Detroit River.
He had the pole in the second of two races last year and led 46 of 63 laps. But locked up his brakes late in the race when under pressure from Ryan Hunter-Reay. Rossi ended up overshooting a turn and puncturing a tire, requiring a pit stop, and finished 12th.
The Andretti Autosport driver had a second-place finish at the Indianapolis 500 , coming up just short to Simon Pagenaud of Team Penske.
Alexander Rossi won his second pole of the season, leading qualifying for the first of two Detroit Grand Prix races.
The Andretti Autosport driver, coming off a second-place finish at the Indianapolis 500, turned the fastest lap Saturday in just more than 1 minute and 14 seconds on the 2.35-mile road course.
Josef Newgarden qualified second, followed by Scott Dixon and rookies Felix Rosenqvist and Colton Herta. Indy 500 champion and points leader Simon Pagenaud will start 13th in the 22-car field on Belle Isle.
Rossi has taken advantage of the pole to win four of six races, including this year at Long Beach. Rossi earned the pole at the last race in Detroit, but finished 12th after puncturing a tire.
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