A quite incredible season ended in the most stunning way possible, with City snatching victory from the jaws of what seemed certain to become the most disastrous defeat imaginable.
Second-half goals from Djibril Cisse and Jamie Mackie, either side of a ridiculous Joey Barton red card, seemed to have turned the entire season on its head.
But with the game entering five minutes of stoppage time, City produced a finish equally as memorable as that of Manchester United in the 1999 Champions League final.
That United should be denied just made the joy so much sweeter, as first Edin Dzeko nodded the Blues level before Sergio Aguero collected Mario Balotelli's return pass and drove home the goal that crowned City champions.
Bolton's failure to beat Stoke meant QPR survived anyway, which was the very least their defiant defending deserved in a truly astonishing game.
There is nothing quite like the last day of the season for making the most straightforward of tasks seem akin to scaling Mount Everest.
On the face of it, City, having dropped just two points at home all season, had little to worry about from QPR, who had two points in 11 away games and conceded six at Chelsea a fortnight ago.
For 38 long minutes though, the Blues could not find a way through their opponents' blanket defence.
Mark Hughes had set his side up to spend long periods without the ball and challenged City to find a gap.
David Silva came closest, driving one shot wide, having a near-post effort saved by Kenny and another goalbound strike blocked by Barton.
QPR remained defiant though, if not exactly composed.
It needed something a little bit different for City to open their opponents up. Pablo Zabaleta provided it.
In 152 previous appearances for the club, the full-back had managed just three goals. His last came in May 2011, 35 matches ago.
With a sense of anxiety gripping the stands as news of their temporary status as number two in the Premier League filtered through, Zabaleta scorched in from the right flank.
He kept advancing after laying a pass off to Silva, who in turn fed Yaya Toure.
It meant he was within striking range when Toure flicked the ball through and let fly with a fierce effort towards the far post. TV replays did not do Kenny many favours as the ball slithered through his fingers, but in real-time, the QPR keeper had been exposed and his reaction was not quick enough as he turned and tried to claw the ball out of his goal after it had bounced in off the woodwork.
The stadium erupted. Suddenly, what was happening at the Stadium of Light did not seem quite so important.
Instead it was events at the Britannia Stadium that were of huge importance as, from being in a position of relative comfort in terms of their own top-flight status, QPR were now hanging over the trapdoor, with the famous fat lady beginning to clear her throat.
It meant Mark Hughes, returning to the club that dumped him so unceremoniously in December 2009, knew he could no longer rely on his containment policy, which was both an opportunity for City and a reason to be wary.
And so it proved as Joleon Lescott made a disastrous decision to head Shaun Wright-Phillips' hopeful lofted pass back to Joe Hart. Cisse read it and duly smashed a first-time shot into the bottom corner.
Back came all those nerves, although the worry was soon replaced by fury at Barton's antics.
The one-time City midfielder, whose time at the club was scarred by so many problems, will receive an automatic suspension for elbowing Carlos Tevez in the face, but surely there will be an additional sanction for his attack on Aguero, which was deliberate, as he was ushered from the field, the incident sparking a mass confrontation which substitute Mario Balotelli wanted to get involved in.
The drama had only just begun though. And when substitute Armand Traore skipped past Zabaleta on a rare foray forward, his far-post cross was perfect for Mackie, who launched himself at the ball with a diving header neither Hart nor Lescott could keep out.
Now City had only one course of action open to them.
On came Dzeko, then Balotelli in a frantic attempt to grab a lifeline.
Both came close, Dzeko hitting a post, Balotelli drawing a fine save from Kenny as QPR abandoned any pretext of attacking intent.
It all looked to be in vain as the game entered five minutes of stoppage time.
Even the celebrations at Dzeko's leveller, when there were under four minutes left, were muted.
But when Aguero scored his 30th - and by far the most important and dramatic - goal of the season 120 seconds later, the roof came off the Etihad Stadium.