Dixon finished just two-tenths of a second behind Arrow McLaren’s O’Ward, who punted him out of the Long Beach Grand Prix in April.
The six-time champion was livid with the move, which O’Ward was unrepentant over, and declared: “If that's how the series wants us to race, then I guess it's all gloves off from this point.”
Having chased down O’Ward in the closing laps, Dixon was just unable to get within range to make a move to grab the final spot on the podium.
When asked by USA if he was tempted to get physical, he replied: “That day will come! We’ll see. But I think there’s a time and a place for it.
“We were trying to get close and he had more OT [push-to-pass allocation] than us. For the most part, we tried to race as cleanly as possible.”
Source: Autosport