Mercedes says that Paddy Lowe's involvement in the radio instructions to Lewis Hamilton during the Abu Dhabi Grand Prix was proof that the situation had reached "the highest escalation" possible.
After Hamilton ignored various instructions to pick up his speed from his engineers, Mercedes executive director Lowe came over the radio to urge Hamilton to go faster.
"We need you to pick up the pace," he said.
In response, Hamilton again declined to pick up his pace and said: "I'm in the lead right now. I'm quite comfortable where I am."
Speaking afterwards about how the events unfolded, Mercedes motorsport boss Toto Wolff explained that having Lowe issue instructions was significant.
"Paddy with the instruction is the highest escalation we have in the rules of engagement," he said. "We have invented those rules of engagement together, a while ago, in Melbourne, on the table."
When asked if he himself considered issuing instructions, Wolff said: "No, because I haven't got the button to do that. I know myself, there is a risk I would do it, and I would have done it on several occasions in the past, and maybe regretted it afterwards.
"You know the famous Wolfgang Ullrich thing in Austria [relating to an instruction to take out an Audi rival]. You need to know yourself, and your strengths and weaknesses, and I know my weaknesses."
Although Wolff had said before the grand prix that Mercedes would not interfere in the battle between its drivers, he explained the radio messages to Hamilton came about because the team feared it was going to lose the grand prix to Ferrari.
"There were two moments in the race when there was a risk strategy that we would be losing the race. One was [Max] Verstappen, because it was not clear whether he was on a one stop; he was in a good position.
"The other was [Sebastian] Vettel lapping two seconds quicker. Our number one principle for the past three years – and this doesn't matter if it's the first race or the last – is to secure the win.
"You can question that, whether it's the right principle going forward, but that's exactly what we did on the pit wall – there were these two moments and this is why we asked him to increase the pace."