APRIL 27: When the legendary Italian manager, 62, turned to his Real Madrid backroom staff with arms outstretched and gave an anxious glance down at his watch with City 2-0 up after only 11 minutes on his return to Etihad Stadium, he was probably fearing a similar scoreline.
City were flying. Real were overwhelmed. This was shaping up as a one-sided mauling for the great old Champions League campaigner chasing the trophy for a historic fourth time.
And yet, to the disbelief of pretty much everyone who witnessed a gold standard classic of a football match, Ancelotti was pitchside after the game smiling, eyebrow raised in trademark fashion suggesting he was rather happy to come away with a 4-3 first leg loss.
He did not look as mystified as others at the fact that Real were still in with a shout of reaching yet another Champions League Final.
City's players were not exactly deflated - how could they be after such a brilliant performance and a semi-final first leg win? However, their body language gave away the brutal fact that they should have had this tie all wrapped up heading into the second leg in the Bernabeu.
This was a breathless night, everything that is good about football at this rarified level and City were, at times, magical.
The Bernabeu does strange things in the Champions League and, while City are unlikely to endure the same physical onslaught Atletico Madrid subjected them to in the quarter-final second leg, they will face a severe test with just a one-goal lead.
City let Real off the hook and history tells us this can be a very expensive mistake.
Ancelotti, as well as many of this Real squad, have been over this course and distance before though they will also know they were ripped to shreds for long periods of this game.
But they will also have serious belief they can go through to face either Liverpool or Villarreal in Paris.
The good news for City is that, despite the narrow scoreline, there were times when they outclassed Real, with Luka Modric unable to exert his usual influence in midfield.
City were quicker, slicker, better, more threatening. This is the knowledge they will pack with them on the flight to Madrid.
Who knows what sort of lead it takes to finish Real off, backed by the Bernabeu crowd and such a rich history in this competition? Every big night in the grand old arena is accompanied by sense of destiny.
A glimpse of Guardiola's mindset came with City two goals up and Real pretty much floored.
The Spaniard flew into a full-on rage in his technical area when Riyad Mahrez committed the cardinal sin in this manager's book by being too greedy, lashing a shot into the side-netting with Phil Foden waiting unattended in the middle and the goal at his mercy. At 3-0 it could have been job done.
"Riyad. Riyad", Guardiola shouted before continuing the fume. He knows you simply cannot give Real a break and the Spanish giants proved that.
City had a two-goal advantage on three occasions, played wonderful, fluent football but will know there should be no need of those nagging doubts that might have been felt at the final whistle.