Birthday boy Daniel Ricciardo has had to pull out of the Austria Grand Prix due to engine issues, but his Red Bull teammate Max Verstappen took advantage of a disastrous double no-finish for Mercedes to win the event.
The No.3 ranked Australian, who turned 29 on Sunday, had to withdraw from the race after completing just 53 laps due to engine troubles.
Lewis Hamilton lost the lead when Mercedes teammate Valtteri Bottas broke down to cause a virtual safety car (VSC) and his own race ended with a late engine failure.
Sebastien Vettel had started his Ferrari sixth, having been penalised three grid places for impeding a rival in qualifying, but fought back to end third. With Hamilton failing to score, Vettel regained the championship lead 146-145.
Ricciardo's teammate Verstappen, who started fourth, held off a late charge from Kimi Raikkonen in the other Ferrari to celebrate his fourth career victory and first of the season.
The triple-header of consecutive French, Austrian and British races concludes next week at Silverstone with the championship now fascinatingly poised.
Mercedes had dominated the 4.318-km Red Bull Ring in Spielberg since the Austrian race returned to the calendar in 2014 and that looked set to continue until an inexplicable error.
When Bottas suffered a failure of hydraulic pressure and lost gearbox function, he trundled to a halt on lap 14.
But while Red Bull and Ferrari quickly brought in both drivers for fresh tyres, the Mercedes garage did not make the same call for Hamilton.
Vettel took advantage of the bad luck of others to make the podium and his result was made even better when Hamilton pulled over on lap 64.
Verstappen had a four-second lead to Ricciardo when he took over the lead and grew his advantage until his teammate, with a blister on his left rear tyre, fell behind Raikkonen.
Ricciardo then pitted at the same time Vettel squeezed beyond Hamilton on the 39th of the 71 race laps.
Verstappen led Raikkonen by more than six seconds but with everyone behind the Dutchman seemingly anxious to protect tyres, he was unchallenged.
Hamilton had to pit again on lap 53 and came out fifth behind Ricciardo but took that place back within a lap when the Red Bull's engine failed to ensure no happy returns on Ricciardo's 29th birthday.
