The IndyCar race in Detroit stops before it really even starts as the pace car crashes into a wall. (1:37)

After his first IndyCar victory since 2015, Ryan Hunter-Reay could look back on some of the most frustrating moments of the drought.

"If you look at the past Indy 500s in '17 and '16, ones I think we could have won -- both of those. Led the most laps in one of them, didn't finish the race," he said. "Catching James Hinchcliffe at Long Beach in the last five laps or whatever it was. The electrical system shuts down. Leading in 2016 at Pocono and the same electrical problem shuts the car down."

Hunter-Reay can finally put all that behind him after he prevailed at the Chevrolet Dual in Detroit - Race 2 on Sunday, taking over the lead when teammate Alexander Rossi slid off the track at a turn with about seven laps to go. It was Hunter-Reay's 17th career IndyCar victory but his first since Pocono in 2015.

Rossi, the pole winner, was struggling to hold off Hunter-Reay before the mishap at a right turn on lap 64 of 70. From there, it was smooth sailing for Hunter-Reay on the 2.35-mile street course. He finished more than 11 seconds ahead of second-place Will Power.

"There was just no way anyone was going to beat him," Power said. "We just seemed to struggle a little bit on full tanks and cold tires, but very happy with the result. You know, I feel like with what we had, that's the most that we could have got out of that race."

Ed Jones finished third, followed by Scott Dixon. Rossi fell to 12th and dropped out of the series points lead.

"Our car was quick. We led a lot of the race," Rossi said. "I don't have an answer for you, unfortunately."

The race Sunday was delayed over a half-hour because the pace car, driven by General Motors executive Mark Reuss, crashed during a pace lap.

Chevrolet said in a statement that there were no serious injuries:

"We are thankful that there were no serious injuries. Both the pace car driver and the series official were taken to the infield care center, where they were checked, cleared and released.

"It is unfortunate that this incident happened. Many factors contributed, including weather and track conditions. The car's safety systems performed as expected."

Ryan Hunter-Reay celebrates his victory in Detroit on Sunday, his first IndyCar win since 2015. AP Photo/Carlos Osorio

Mark Sandy, a manager with IndyCar, was a passenger in the car.

"I think that's a testament to the Corvette ZR1. I know that thing is 750 horsepower,'' Hunter-Reay said. "I've driven one before, and you do not want to jump on the gas in that thing, and for sure it's a fast car. ... It's something that can happen, and the race hadn't started. No big deal.''

Rossi and Hunter-Reay both drive for Andretti Autosport.

Power, this year's Indianapolis 500 champion, returned to the top of the season standings. He had fallen from first to third after Saturday's race, in which Dixon outlasted Hunter-Reay for the win.

The second half of Belle Isle's IndyCar doubleheader was Sunday. After the delay following the pace car crash, there was another caution right after the start when Spencer Pigot spun. And after that, the race was caution-free the rest of the way.

Rossi led by 8.1 seconds with 16 laps to go, but Hunter-Reay quickly closed in. He trailed Rossi by 2 seconds with 10 to go, and the margin was 0.27 after lap 63.

Rossi hit the brake before a turn and his front left tire appeared to fail him, then his car went straight toward a runoff area.

"Alex has done a great job, no doubt a future series champion," Hunter-Reay said. "My job is to make sure it's not this year."

The Associated Press contributed to this report.