Lewis Hamilton has suffered a dent in his championship hopes after rival Sebastian Vettel held off Ferrari team-mate Kimi Raikkonen to win the Hungarian Grand Prix on Sunday.
Hamilton finished fourth after he allowed his Mercedes team-mate Valtteri Bottas past him on the last corner.
Mercedes had earlier ordered Bottas to move out of the Briton's way in hope that he would be able to find a way past Raikkonen and potentially Vettel, too.
But after Hamilton failed, he sportingly let Bottas back past to finish off the podium and lose further ground to Vettel in the title race.
Hamilton will now head into the sport's summer break 14 points behind Vettel in this most topsy-turvy of championship battles.
Hamilton started only fourth on the grid and he was down to sixth following the 610-metre dash to the opening corner after he was gobbled up by both Red Bull drivers.
Max Verstappen made his move round the outside of Hamilton, with Daniel Ricciardo diving underneath the British driver.
Verstappen however, ran wide at Turn 1. He rejoined the circuit alongside Ricciardo and at the left-handed Turn 2 the Dutchman went in too hot on his brakes and inexplicably thudded into his Red Bull team-mate.
The force of the impact tore through Ricciardo's Red Bull bodywork and into the radiator, and the Australian spun on his own fluid before grinding to a halt.
Ricciardo was furious: "Was that who I think it was?" "Yes," his Red Bull team replied. "F****** sore loser."
"It was amateur to say the least," Ricciardo said on his return to the paddock. "There was no room to pass. Valtteri was in front and I was on the outside so there was no room.
"You've got the whole race to try and repair the mistake but the pass was never on. It wasn't even a pass. It was a very poor mistake.
"There isn't an excuse for it. He sees me go past and thinks 'I've got to fix this' and then we crash."
The safety car was deployed to deal with Ricciardo's stricken car, and Verstappen, who escaped the incident without any damage, was handed a 10-second penalty for causing a collision.
Four laps later the safety car pulled in and the race was back under way. Vettel soared off into the distance with Raikkonen in second, and Bottas a distant third.
Hamilton appeared to be struggling for pace, and began falling off the back of Verstappen's gearbox. Then, his Mercedes team were hampered by a radio issue.
Hamilton's engineer Pete Bonnington could contact the Briton, but he was unable to communicate back.
The leaders all pitted for their one and only change of rubber in and around half distance, and it was then that Vettel, who had appeared in control of the race, reported a steering issue.
Vettel claimed his Ferrari was veering to the left in a straight line and suddenly Raikkonen was within one second of his Ferrari team-mate.
With Verstappen out of the way following his timed penalty, the Mercedes pair closed in on the Ferrari drivers, too, and by lap 40 of 70, both the two Ferrari and two Mercedes cars were separated by just five seconds.
Suddenly, Hamilton's radio came back to life.
"I've got a lot of pace now so let me use it," he said angling for Mercedes to pull Bottas out of his way and launch an assault on the Ferrari duo. "If I can't catch the Ferraris I'll let Valtteri back past," he added.
Moments later on lap 46, Hamilton got his wish, with Bottas moving out of his way at Turn 1.
"We have got five laps to make something of this," Hamilton was told. "No pressure, then," came the reply.
Hamilton got close to Raikkonen, but could not get past the Finn with overtaking notoriously difficult at this twisty Hungaroring circuit. He then offered to let Bottas back past, but his Mercedes team handed him another five laps.
Again, Hamilton could not get past, and with Bottas seven seconds behind his Mercedes team-mate it looked as though he would finish third.
But Hamilton dramatically slowed down on the final lap to allow Bottas back through.
Verstappen finished fifth, just 0.3 sec behind Hamilton, with Fernando Alonso sixth for McLaren. Britain's Paul di Resta, standing in for Felipe Massa at Williams, retired in the closing laps with an oil issue.