Lando Norris defended his controversial move on Oscar Piastri after he was accused by the Australian of doing a "s---" job in avoiding their first-lap collision in Singapore.
As George Russell delivered a faultless performance from pole position to land his second victory of an impressive year, Norris' simmering rivalry with McLaren teammate Piastri finally boiled over when they banged wheels at the third corner.
Norris, who started two places behind Piastri, was half-a-car's length alongside his teammate at Turn 2 before he launched his move at the ensuing left corner. Norris tagged the back of Max Verstappen's Red Bull and the contact sent him into Piastri and then ahead of his teammate.
Piastri's plea to McLaren to reinstate the positions fell on deaf ears. Piastri crossed the line in fourth with Norris, a place ahead in third, reducing the championship deficit from 25 points to 22.
Verstappen, runner-up on the day, is a further 63 points off the championship pace with 174 points still to play for across the concluding six rounds.
"Anyone on the grid would have done exactly the same thing as I did so if you fault me for just going on the inside of a big gap then you should not be in Formula 1," said Norris of his opening-lap move. "There was nothing wrong with what I did.
"I misjudged a little bit how close I was to Max, but that is racing and I would have ended up ahead of Oscar anyway. I was on the inside and the last thing I want to do is to make contact with my teammate.
"With the position I am in [in the championship] I cannot afford to do that compared to him. I put myself at risk if that kind of thing happens. The FIA thought it was fine and the team did so too."
The stewards noted the collision between the Papaya drivers but elected against any action.
"That wasn't very team-like, but sure," protested Piastri on the radio. "So we are cool with Lando just barging me out of the way?"
Piastri was informed by race engineer Tom Stallard that McLaren were looking into the flashpoint before he delivered the news his driver did not want to hear.
"As a team we can see that Lando has to avoid Verstappen, so we won't take any action during the race," said Stallard. "We can review further afterwards."
Piastri was not impressed, adding: "Mate, that is not fair. I'm sorry, that is not fair."
Stallard replied: "Oscar we will have the opportunity to review together afterwards. Focus on this race, mate. We can still get a good result here."
Piastri bit back: "Yeah, but if he [Norris] has to avoid another car by crashing into his teammate, then that is a pretty s--- job of avoiding [me]."
Speaking after the hot and humid contest in the city state, a more considered Piastri said: "I need to look more at the replays and in more detail and come to my conclusion then.
"In the moment, it is the first lap, tensions are high and we are encouraged to share our views on what happened. I did that and we will discuss it moving forward."