Pep Guardiola was left 'emotionally destroyed' and aged 10 years even though Manchester City swatted aside Bayern Munich last night.
Rodri, Bernardo Silva and Erling Haaland gave City a sizeable three-goal advantage going into next week's Champions League quarter-final second leg in Bavaria.
Guardiola warned his squad that the job of securing a last-four spot is not complete but praised the attitude of his players after a dramatic night at the Etihad Stadium.
'It was not comfortable - emotionally I'm destroyed,' Guardiola said. 'I have 10 more years today. It was such a demanding game.
'I know exactly what we have to do there. If you don't perform really well they are able to score one, two, three. I know that. The players know that. It's an incredible result, but we have to do our game with huge, huge personality.
'We are going there to score goals. It's an incredible result. I had a feeling that we had our chance in our stadium, we have [created] something special here this season.
'It was a tight game for 60 minutes. For part, they were better than us. There are teams who won that had less chances than Bayern did today.
'Bayern have been outstanding, I've been there many times. In Europe they are special. You need to do a really good two games to knock these teams out, not just one.' Haaland became the first Premier League star ever to score 45 goals in a single season when he netted the third after a clever assist for Silva's header.
'Bernardo is one of the best players I've ever trained in my life,' Guardiola added.
'Special. Erling is always a threat. First half he wasn't in the game, [Matthijs] De Ligt always beat him with the long balls. When we started to play better he did. He's not just a scorer, he helped us a lot.'
Bayern boss Thomas Tuchel insisted that the three-goal deficit was unjust, although criticised individual mistakes - particularly by centre half Dayot Upamecano for Silva's goal.
'He will learn,' Tuchel said. 'Now I try to not allow my players to focus on the score because it doesn't tell the story of the match. That is the challenge, to focus on the things we did well.
'We played with personality and courage. Everybody is disappointed. It's a mixed feeling: I think the players felt that it doesn't feel like a 3-0. It's a huge task to turn it around. We will not give up but are realistic. It will not be over until we are in the shower.'