A highly contentious five-second penalty robbed the Ferrari driver of victory.
With Leclerc on fresher tyres than his teammate, things threatened to go from bad to worse for Vettel as Leclerc was closing in towards the end of the race.
"We had some issues with Lewis's vehicle before the race and this actually became apparent after qualifying", said trackside engineering director Andrew Shovlin in Mercedes post-race Pure Pitwall debrief.
Brawn, F1's managing director, also likened the decision-making process - and the "transparency" that is required - to the use of VAR in football.More news: Manchester United complete signing of Welsh winger Daniel James
But throughout this string of dominance that has the Brackley-based team poised for their sixth consecutive constructor championship and has Hamilton poised for his third consecutive driver championship, his fifth driver championship in the last six seasons and the sixth driver championship of his career, Mercedes have not been shy about playing the underdogs. Vettel countered that he had nowhere to go and was battling to keep the auto out of the barriers, with no idea where the Mercedes was. Where, as he asked, could he have gone?
Vettel had started from pole position and crossed the finish line narrowly ahead of Hamilton.
Where is the consistency? We were able to get the auto back together. "They have decided it is a five-second penalty".
Drivers are unanimously up in arms. But the stewards decided Vettel's action was unsafe and applied a five-second time penalty, plus two points on his super licence.More news: Amanda Knox arrives in Italy to attend discussion on wrongful convictions
Vettel was in no mood to play nice.
Okay, maybe there was some doubt about whether the vehicle would be up to its usual standards, as the team did have issues with it earlier in the weekend, including issues stemming from a hydraulic leak that they discovered after qualifying the night before the race and had to fix on Sunday morning. Montreal erupted in thunderous applause.
"Therefore, it might be useful to work with the FIA on solutions that would allow the stewards to explain their decisions to the fans and to elaborate on how they reached them". Stand by your call, Lewis. If you make it by, great, if you don't make it by, missed opportunity.
Vettel interrupted, asking the audience not to boo Hamilton. "Obviously, I was going through the grass and I think it's quite commonly known that the grass isn't very grippy, and then I was coming back on track and just trying to make sure I had the auto under control". Ayrton Senna would be proud. While there was hardly any dearth of drama at the just-concluded race at Canada, given the Hamilton and Vettel episode, it did seem that Hamilton won a highly-debated contest. With one defiant shuffle of the boards, Vettel put Hamilton in his place.More news: Jenna Fischer wins Stanley Cup war against 'The Office' co-star John Krasinski