Max Verstappen's defence of his first Formula One world championship started in dramatic circumstances as he was forced to retire in the car in the closing laps of the Bahrain Grand Prix.
Verstappen ran second for the entire race and looked well placed to challenge Ferrari's Charles Leclerc for victory at a late Safety Car restart, only to encounter car issues in the closing laps.
An angry Verstappen radio message had already been broadcast earlier in the race, as the reigning champion complained about being asked not to push the tyres too hard on the lap after both his pit-stops.
Verstappen felt that without these requests, Leclerc would not have stayed ahead when he emerged from his own pit-stops.
Verstappen: "OK this is now two times that I take it easy on the out-lap, that I could have been in front.
"I am never, ever doing it again!"
The drama would continue for Verstappen later in the race and once again played out over the radio.
After his final stop, Verstappen started to complain about some odd behaviour from his car's steering wheel, which was later traced to damage sustained to one of its track-rods when the car was dropped off its jacks after the tyre change.
Here are his exchanges with race engineer Gianpiero Lambiase as the problem unravelled in the final portion of the race.
Verstappen: "Mate, my steering wheel is suddenly very heavy..."
Verstappen: "I almost can't steer."
Lambiase: "Let me know if we need to box, Max,"
Verstappen: "No, just f------ tell me what's wrong and I'll try to handle it"
Lambiase: "Max, is the [steering] wheel heavy in both directions, so both left hand and right hand down?"
Verstappen: "Everywhere, everywhere! It's not even smooth. Like I have to *censored by F1* even on the straight"
Lambiase: "We are staying out. We don't believe it is a reliability concern at this stage".
Verstappen: "Yeah... it's more and more difficult to steer with speed"
At this stage, Verstappen appeared to have been put back into contention for victory, with a late Safety Car wiping out the time advantage Leclerc had built up over the race.
As the Safety Car returned to the pits and the race resumed, it was quickly apparent Verstappen was not going to be able to mount a late challenge on Leclerc's lead.
The delayed radio messages continued to be broadcast.
Verstappen: "Mate, what's going on with the battery?"
Lambiase: "Battery fine".
Verstappen: "No, it's not! What the f--- is this?"
Shortly afterwards, another exchange was broadcast as Verstappen was passed by Ferrari's Carlos Sainz. He then slowed dramatically and tumbled down the order.
He would return the car to the pit-lane to retire from the race.
Verstappen: "It's s------ itself!"
Lambiase: "We can see the issue, Max. It's not battery related"
Verstappen: "What do you want me to do?"
Lambiase: "There's not a lot we can do".
The drama continued for Red Bull on the final lap, as Verstappen's teammate Sergio Perez defended third position from Lewis Hamilton.
Perez, who had complained about a loss of power a lap previously, spun at Turn 1 and did not restart the car, meaning Red Bull went from running both cars in the top four to failing to score a single point in a handful of laps.
Red Bull suspects both failures were related to the fuel system on its cars.