Thomas Tuchel reiterated his belief the "unique" Champions League final stood apart from domestic meetings between Manchester City and Chelsea, but another Blues win gave his side confidence.
Three weeks on from knocking City out of the FA Cup and ending their quadruple bid, Chelsea defeated the Premier League leaders again.
Tuchel's men trailed to Raheem Sterling's goal a minute before half-time and then escaped further punishment when Sergio Aguero made a mess of a penalty moments later.
Chelsea regrouped at the break and responded with goals from Hakim Ziyech and Marcos Alonso to win 2-1.
Tuchel, who lost his first three coaching duels with Pep Guardiola in Germany but is unbeaten in four since, told Sky Sports: "Sure, it gives us confidence, because it's all about performance and confidence.
"We know very well, I've said it before and I will repeat it, that will not change the final. It's a very unique game. We cannot predict what will happen, so you need to be well prepared
"We will have some changes again and they will have some changes again, but we arrive with the knowledge that we are capable of beating them. This is what we have now and this will not change until Istanbul."
Chelsea had 43.3 per cent of the possession in the first half but 57.9 per cent in the second, while four of their five shots on target came after the restart.
Tuchel highlighted "more control" as key in their improvement, while Ziyech's goal allowed the team to get "more and more confident".
"What a performance in the second half," he said. "It was more or less an equal first half. In the last five minutes, we had to give it away completely.
"If they score the penalty, maybe it's over before it really starts. Maybe you go to half-time at 2-0 and you have no chance to come back.
"But it was very hard because we were 1-0 down and had one injured player, so I am absolutely impressed by the reaction and the performance in the second half.
"I think we even deserved to win with the performance in the second half.
"If you want to steal all three points at Etihad in this situation, after being 1-0 down, you need a bit of luck, a bit of momentum and decisions from referees. It's like this.
"But we had many, many half-chances, many chances here in the second half. Big, big congratulations to the team for the second half."
It was the first time in 10 attempts Chelsea had won after trailing at the interval in the Premier League.
The Blues had rescued just two draws since a comeback victory against Aston Villa in June 2020, losing on the other seven occasions.