The old school set it up, the new school finished it off.
Sergio Aguero and Ilkay Gundogan laying the foundations for the first victory of another Champions League campaign for Pep Guardiola, Phil Foden and Ferran Torres combining to decorate it in some style.
The third goal of a triumph that was occasionally laboured will have sent Pep home happy.
He loves that sort of stuff.
Foden with the ultra-intelligent assist, Torres with the dart inside and emphatic finish, both of them 20 years of age.
It gets Guardiola to the training ground every day and gave the sort of comfortable look to the scoreboard that City’s performance did not always look like producing.
Indeed, if you had wanted a snapshot of why City have not won the Champions League under Guardiola and will probably not win the Champions League under Guardiola, it was provided early doors.
Provided by Ruben Dias in his casual gifting of possession to Matheus Uribe, provided by Joao Cancelo in his derisory attempt to hinder the rapid progress of Luis Diaz.
Ederson had little chance with the Diaz strike but the goal was trademark City, trademark ropey defending despite the hundreds and hundreds of millions of pounds spent.
Ironically, Dias looks the sort of defender many think City have been crying out for.
Uncompromising, physically imposing. But when Guradiola starts asking him to knock it out from the back like Beckenbauer, that is when the trouble will start.
In Porto’s books, it will go down as a splendid individual effort but it was an effort Champions League winning teams do not concede.
Thanks to Ederson’s casually errant distribution, City almost conceded another soon after but, by then, they were level, courtesy of Aguero’s penalty.
Pepe, as Pepe does, committed a couple of offences in one clumsy confrontation with Raheem Sterling and Aguero’s hit squeezed under Agustin Marchesin.
It was the sort of penalty, and goal, City might concede and, to be fair, they needed as much help as they could get, particularly with their propensity to turn the gun-barrel to their own feet.
Classically, just before half-time, Kyle Walker had to clear off the line from Cancelo.
This was not City’s first choice defence but even a fit Aymeric Laporte is not a panacea for its ills.
The only panacea Guardiola knows is attack. Defence by attack. Defence by possession. Defence by creativity.
His problem for much of this game – certainly an issue before the introduction of Foden and Torres – was that there was not enough of the latter.
Having said farewell to David Silva, the absence of the injured Kevin de Bryune was, and will be, painfully felt.
The struggle to create clear opportunities must have been alarming at times for Guardiola.
But he has plenty of players who can produce moments of quality and one of them is certainly Gundogan.
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He won the free-kick and converted it with the type of strike some keepers might keep out. Porto’s Marchesin is not some keeper.
That heralded a couple of City changes and the pair combined for the moment of the night.
It was the sort of moment that will have Pep thinking it might just happen this time around.
You never know.
Who will win the Champions League? Have your say in the comments below
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