Not even the sending-off of Bayern defender Jerome Boateng four minutes from time for bringing down Yaya Toure could stop Guardiola celebrating his team's "best game" in his few months in charge of the Bavarian giants.
"I'm lucky to be here and training these players," said Guardiola, who won the Champions League in 2009 and '11 with Barcelona.
No team has retained the Champions League since the format's inception in 1992. On this evidence, it will take some stopping Bayern breaking that record.
The scoreline flattered City, whose 4-1 victory over Manchester United in the Premier League 10 days ago must seem like a distant memory.
After starting its Group D campaign by beating CSKA Moscow 3-0 at home, it was thought Bayern would be given a stern challenge at the Etihad Stadium by a side which has title pretensions of its own and which also opened up with a 3-0 win, at Viktoria Plzen.
Not a chance.
At times, it got embarrassing one-sided. City's fans even clapped Bayern's players midway through the second half and applauded the untouchable Robben when he was substituted in the 78th.
"That is why they are champions," City defender Micah Richards said. "It felt like they had an extra man."
Playing with Thomas Mueller in a withdrawn role on his own up front, Bayern always had extra numbers in midfield just as Guardiola craves and was first to every ball. Philipp Lahm, a full back playing out of position as a holding midfielder because of injuries in the squad, looked like he had been playing there all his life.
It was all very familiar for City manager Manuel Pellegrini, who looked part-flabbergasted, part-resigned as he stood in the technical area with his hands in his pockets throughout. When he came up against Guardiola's all-conquering Barcelona side in his stints in Spain with Villarreal, Real Madrid and Malaga, Pellegrini lost seven of eight games and drew the other.
Both are coaching in different countries now, but nothing has changed.
City, constantly overrun in midfield by playing two up front, was its own worst enemy at times, as demonstrated by Hart's error for Ribery's goal.
The France winger cut inside to get half a yard on Jesus Navas and unleashed a powerful, low shot from outside the area that Hart should have kept out. Instead, but he only palmed the shot into the roof of the net.
Hart's status as England first-choice goalkeeper is already under threat after mistakes this season for the national team in a friendly against Scotland and for City in a Premier League defeat at Cardiff.
Torn apart time and again, City somehow turned around only 1-0 down. The pattern of the game continued after the break, though.
Moments after Robben curled a shot just wide in the 54th, Dante picked out Mueller with a long, diagonal ball forward and the Germany forward enjoyed the freedom of the area to round a stranded Hart and tap home. Gael Clichy, who had been marking Mueller, initially switched off and then curiously chose not to follow the run.
It got worse for City. Toni Kroos dispossessed Fernandinho in the center circle and fed Robben, who sprinted toward Matija Nastasic, turned the center back inside out and buried a right-footed shot past Hart at his near post.
After Mueller came close to making it 4-0 by crashing a shot against the goal frame, Negredo finally sparked some panic in Bayern's defense by curling home a fine finish and City even smelt a miracle comeback when Boateng was given a straight red for tripping the below-par Toure as he charged through on goal.
David Silva struck the crossbar with the resulting free kick and Bayern saw the game out.
"I think we played really bad," Pellegrini concluded.
By picking up just three points in its group last season, City delivered the worst campaign by an English team in the history of the Champions League but was hoping to finally make a statement of intent this time round after spending nearly 100 million pounds in the offseason.
They are nowhere near Champions League contenders on this evidence.
