Charles Leclerc criticised his Ferrari Formula 1 team for an "unfair" decision in the Singapore Grand Prix after falling behind eventual winner Sebastian Vettel.
Poleman Leclerc led the opening phase of the Marina Bay race, as he slowed the field up in a bid to keep his tyres alive for as long as possible.
Ferrari elected to pit his team-mate Vettel, who had been running third, one lap before Leclerc.
The early stop on fresh tyres handed Vettel enough of a pace advantage over one lap to jump Leclerc with the undercut.
Speaking over the team radio during the first safety car phase, Leclerc made clear that he was not happy with what happened.
Having been urged to concentrate on the race and 'keep his head down', he replied: "My head is down and it will be down until the race [is done] - I just want to let you know my feelings.
"To be completely honest with you, I don't understand the undercut - but we will discuss after the race."
Later on, during the second safety car phase, Leclerc responded to a message from the team telling him to look after his engine - an instruction that effectively called off the intra-team fight.
Responding, he said: "Yep. I won't do anything stupid. It is not my goal. I want us to finish one-two. I just don't think it is fair. But I won't do anything stupid."
After the race Leclerc reiterated that he would speak to the team later on, and explained that while the situation was hard, he was at least happy Ferrari got its first one-two of the season.
"Obviously it is always difficult to lose a win like that, but in the end it is one-two for the team so I am happy for that," he said.
"It is our first one-two of the season, and all the guys deserve it.
"We arrived here hoping for a podium and we come back with a one-two so I am happy.
"I am disappointed on my side as anyone would be. Sometimes it goes that way, but I will come back stronger."
Race winner Vettel said the strategy call had been made by the team, as he got a very late warning to come in for fresh tyres.
"I think just the corner before, Turn 21, so the last turn before the pit entry, I received the call," he said.
"I don't know if someone pitted for me [to trigger it], but it worked today so I am happy."