"Perhaps the secret is having fun with football and then being ready when I get there. I hadn't played a full match for two months, but I had some great service tonight and an incredible evening," grinned the 36-year-old.
"I was a little afraid of my form seeing as I was out of practice, so to score two Champions League goals was wonderful.
"I just want to be ready when needed, so at my age these nights are brilliant. I can prove that despite it all I am still here and useful to this Milan side, which makes me very happy.
"I have immense fun and the day I retire will be extremely difficult for me."
The first goal was marginally offside, but Inzaghi is an old pro with such incidents in a match situation.
"Sometimes I had goals chalked off by mistake, so it's swings and roundabouts. The fact remains we had to win this game and it was not easy in Marseille."