Manuel Pellegrini deserves praise for reaching the Champions League's last 16 but, unlike Mancini, he had the luck of the draw
This was a defining night for the new Manchester City. Win and the promised land of the knockout stage would be reached. Fail to do so and the risk was that the old Champions League demons might swarm into players' minds again.
Only three minutes were needed to suggest this would be a celebration enjoyed at a canter, 16 more to confirm it as Manuel Pellegrini's men went two-nil up against CSKA Moscow.
Sergio Agüero scored both goals, the first a penalty, the second a measured finish that gave Igor Akinfeev no chance and sealed City's passage to February when the competition gets serious.
To qualify with two games to spare was a resounding riposte to the disappointment of previous forays among the continental aristocrats and the 3-1 dismantling here by Bayern Munich in early October.
The measure of the transformation engineered by Pellegrini could be found in the number of points City held going into last season's fourth match under his predecessor, Roberto Mancini: one.
Going into this one, Pellegrini had secured six, so the completion of the double over Leonid Slutskiy's side will allow City to focus on the Premier League until the new year.
For a club that had failed to survive in their two previous attempts this was dreamland, and would have the Abu Dhabi hierarchy backslapping at the decision to replace the temperamental Mancini with Pellegrini.
With his cool-hand-Luke demeanour and proven Champions League pedigree the Chilean was touted as the dream ticket. He was the anti-Mancini, who oversaw last term's campaign horribilis that ended with no wins and City bottom of Group D as the Italian started the season-long pattern of upsetting many of his star turns.
The rejuvenation of Samir Nasri under Pellegrini is a prime illustration of what man-management can achieve. The Frenchman has gone from the footballer Mancini wanted to hit to a contender for City's player of the season so far under the new manager.
Nasri, on song, can be mesmeric. He illustrated this when he beat Zoran Tosic and Kirill Nababkin inside the area with a soft-shoe shuffle that left them, and the crowd, wondering how he had done so. This allowed Nasri to play in David Silva, the other chief conductor when City pour forward in the kind of symphonic mode that took apart Norwich City 7-0 here on Saturday and Manchester United 4-1 earlier in the campaign.
With Yaya Touré, Agüero and Álvaro Negredo, who scored a hat-trick, the other members of City's attack pack, Pellegrini also insists his side harry when without the ball. It is not that Mancini did not also require this. The point here is that the squad he left behind plus the summer acquisitions, Fernandinho, Negredo and Steven Jovetic (when fit) are responding far better under Pellegrini.
As with the win over United, the display against Norwich was the blueprint of the performance Pellegrini wants each week. "It was a really great performance. What was extra pleasing is that we played really well during the whole 90 minutes, not just the first half," he said before kick-off here.
"Usually a team stops after being 4-0 up at half-time but the team kept playing and that's very important to me. We moved the ball quickly and with purpose and when we didn't have possession we closed the space down quickly and won the ball back. That is what I want from my team. When we play a high-tempo pressing game and then use our ability to move the ball rapidly we are a very dangerous side."
What Pellegrini also has that Mancini lacked in this competition is a healthy portion of luck, with the Italian having a case for saying he suffered ill fortune in each group-stage draw.
While this phase also has the unheralded Viktoria Plzen and the holders, Bayern Munich, City's 2011-12 group featured Bayern, Napoli and Villarreal, and last season's had Real Madrid, Borussia Dortmund and Ajax which made for a quartet of domestic champions vying for two spots. Yet the recording of no wins against any of them home or away, compounded with the failure to beat either Bayern or Napoli when it mattered two years ago, is the true story of why City – and Mancini – fell down.
Now Sheikh Mansour's billionaires become the opposition all others would rather avoid in the two-legged phase. And with Pellegrini having taken two of Europe's lesser lights to a semi-final and two quarter-finals in previous years, who knows how far City may go?
He says: "What I achieved with my previous clubs Málaga and Villarreal shows what can happen in the knock-out stages."
In the two goals City allowed Seydou Doumbia there was a hint of the complacency that Pellegrini remains wary of. "What we must always do is concentrate from the first whistle to the last and never take anything for granted," he says.
There is now time to work on this and any other flaws.