Manchester City discovered the path.
It's called 4-3-3 and it's the formula for nitroglycerin.
It is capable of destroying any defensive organization that comes its way but, misused, it can also demolish the team itself.
Guardiola has an advantage: there has never been a more skilled teacher to use it.
After a mysterious resignation interval, the technician returned to the habits that made him great by equipping the team with the necessary architecture.
After a few hesitant first minutes that cost them a goal, City came back against Porto, clearly dominated and even gave the impression of being released when Ferran Torres scored the final 3-1 after outwitting Pepe in the area.
After the season of extreme experiments, Guardiola seems to inaugurate a new stage.
Back in the Champions League, the coach dusted off the old manuals.
He placed Rodri as the sole midfielder and ordered Gundogan and Bernardo Silva to deploy in more advanced positions, where the interiors again swapped with wingers Sterling and Mahrez.
The old structure injected proteins into a team that has languished for months.
The City started playing well in jerks.
It lacked fluency because the players have lost faith and daring based on speculation, calculation, countermarches.
M. CityEderson Moraes, Walker, Rúben Dias, Cancelo, Eric Garcia, Bernardo Silva, Rodrigo (Fernandinho, min. 84), Gündogan (Foden, min. 67), Mahrez, Sterling and Aguero (Ferrán Torres, min. 67) OportoMarchesín , Jesús Corona (Nanu, min. 76), Pepe, Zaidu Sanusi, Mbemba, Malang Sarr (Evanilson, min. 79), Fabio Daniel Vieira (Mehdi Taremi, min. 76), Sergio Oliveira, Luis Díaz (Wilson Jancó, min. 54), Mateus Uribe and Moussa Marega
13: Luis Díaz.
72: Ferran Torres.
Referee Andris Treimanis Yellow cards Walker (min. 27), Bernardo Silva (min. 33), Cancelo (min. 35), Eric Garcia (min. 66), Pepe (min. 83) and Fernandinho (min. 89)
The City players struggle to believe again.
They are torn between certainty and doubt.
This is how they expressed it in the first half hour of the game, as they tried to put together the plays from behind without defining themselves: are we proactive or reactive?
It was difficult for them to find points of support.
They groped for each other.
Rodri permanently hidden among the Porto strikers, his teammates behind were blind.
Ederson, Eric García and Rúben Dias scanned the horizon trying to send the ball to a safe destination and if Gundogan or Bernardo Silva did not come down to volunteer, it was all clouds and threats of counterattack.
At a quarter of an hour Rúben Dias put in a pass and Uribe intercepted it near the midfield line.
The Colombian instantly played with his countryman Luis Díaz, who began his particular career towards glory.
After flying ahead of Rodri, Eric and Cancelo, he crossed the shot to the net.
The 0-1 had an invigorating effect on the harrowing City.
"Tell Gundogan to go to the extreme!" Guardiola yelled at Eric.
It was like listening to the chords of the old song.
Suddenly, even the insecurity of the defenses began to dissipate.
Every time Gundogan and Bernardo Silva moved between the lines offering associations to the extremes, the defense that Pepe ruled at the other end of the field trembled.
So the penalty was produced, before half an hour.
Pepe dropped Sterling after a shot from Gündogan and Agüero executed it: 1-1.
After half-time, Gundogan scored from a direct free kick after the progressive harassment of Marchesín's goal.
Saved in the line by a shot from Marega, City grew in confidence.
Gundogan forced Marchesín to a stretch before Ferrán Torres, who came in through Agüero, broke the game.
The Spanish winger threw down a wall with Foden and sped into the area like a bullet to collect the return.
When Pepe came out at the crossroads, he broke him with his waist and finished off alone.
Liverpool are rehabilitated
The 3-1 was celebrated as the liberations are celebrated.
The players huddled together and hugged each other with cries of relief.
Not because the ordeal of putting up with Pepe lost, stamping his feet, had ended, but because they had finally found themselves in the 4-3-3 framework.
After all, Guardiola and the double pivot was an impossible wedding.
"What Phil [Foden] and Ferran did was incredible," Guardiola congratulated them in the press conference he gave after the evening.
“Ferran has a great sense of goal.
He's a guy who really moves very well ”.
"We knew how difficult it would be because Porto and Benfica are the best teams in Portugal," observed the coach.
“I was surprised at how defensive they were.
But in the second half we didn't concede counterattacks, we didn't give them set pieces, nor did we let them run.
We did a perfect performance against a really good team. "
In the other Group C match, Olympiakos defeated Marseille (1-0);
while in Group D Liverpool beat Ajax in Amsterdam with a goal against Tagliafico (1-1) and Atalanta thrashed Midtjylland (0-4).