On lap 20, O’Ward dived down the inside of six-time IndyCar champion Dixon in Turn 8. It was a very late manoeuvre, but the Arrow McLaren driver's wheels were fully alongside those of the Ganassi car. The pair made contact that sent Dixon spearing into the tyre wall.
"I was on the inside, he decided to stay on the outside, and I'm pretty much alongside him,” said O’Ward who has four IndyCar wins to his name. “I've been racing Scott for a few years. If he feels like it's my fault them I'm sorry he feels that way. I don't agree.”
He later added: “I'm not going to apologise for that. We're racing. If you're on the outside you're more vulnerable to those things happening.”
Dixon, who would later retyre due to lack of oil pressure – his first DNF in 24 races – had no doubts that O’Ward was at fault.
"[The move] seemed extremely late,” he said. “I wouldn't have chosen to do that. If that's how the series wants us to race, then I guess it's all gloves off from this point."
Following a restart, O’Ward would make an overambitious manoeuvre, again at Turn 8, where he nudged Kirkwood, the impact tipping his McLaren into a spin into the tyre wall.
“The other issue I had in Turn 8 was completely my fault,” he said. “I let my team down, and the amazing crowd that came out today.
“By the time I remembered to stop the car, it was already too late. I didn't want to take out Kirkwood, so I slammed on the brakes and spun.
“I'm disappointed with myself to be making those stupid moves. Not up to the level that I expect from myself."
O’Ward, who finished second in both the opening races of the IndyCar season, eventually finished 17th and on the lead lap, but has now dropped down to second in the championship behind Chip Ganassi Racing’s Marcus Ericsson.
One of his Arrow McLaren teammates Felix Rosenqvist finished seventh, while the other, Alexander Rossi, was running sixth until the final lap when he slithered down an escape road. He was classified 22nd.
