Ibrahimovic captained Milan to a 3-1 defeat at Udinese on Saturday.
Having recently returned from a nine-month knee injury layoff, Ibrahimovic started for the first time this season and briefly restored parity for Stefano Pioli's side from the penalty spot on the cusp of halftime.
Udinese would go on to score two more goals and inflict on Milan their seventh league defeat of the season.
Aged 41 years and 166 days, Ibrahimovic's retaken penalty saw him overtake Alessandro Costacurta(41 years and 25 days) as the Italian top flight's oldest scorer.
"It would have been much better if Costacurta had kept this record," Ibrahimovic said to Sky Sport Italia after the game.
"I am proud to enter the history of this club which is a great club where many great players have passed and that means a lot to me.
"This goal didn't bring three points in my first as captain and unfortunately the game didn't go as we wanted. I felt very well, I haven't played in the starting line-up for 14 months, the important thing is to feel good and if I'm as good as today, I can play, I have no doubts about that."
"Playing as the Italian champions means that each team faces you as if it were a final, it's different from last year," he added.
"This year we have more pressure in all matches, it's normal but you have to be ready because everyone wants to beat you.
"This team doesn't have the experience of playing as champions of Italy, we can't have the same high performance in all the games, but that's not an excuse, it's just an explanation to understand the situation."
