The 31-year-old scored four goals, including a spectacular overhead lob from 35 yards in stoppage time, to help Sweden get off to a winning start at their new national stadium.
“I’m becoming a better player every year,” Ibrahimovic told Champions magazine.
“I won top goal scorer in Serie A and broke the record in Milan for the most goals scored in a season, but I didn’t win anything.
“The question is: ‘Am I happy?’ I’d rather win something playing badly than play well and not win anything, that’s my mentality.”
Ibrahimovic has scored 10 goals in 10 league appearances this term after completing a €20m (£16m) move to Paris Saint-Germain from AC Milan in the summer.
The Sweden captain has won league titles with Ajax, Juventus, Internazionale, Barcelona and AC Milan – and Ibrahimovic insists he has fulfilled all his goals – despite failing to secure a Champions League winner’s medal.
“When I was younger, I’d use different skills and tricks on the pitch because the condition of my body and my movements were very different,” he added.
“I’m 31 years old now and physically much stronger than I was. Players develop over the years – it’s a continual process – and you change your game because you lose speed the older you get.
“As far as dreams go, I’ve done everything I need to do and wanted to do. I haven’t won the Champions League, but whether I do or not, I have reached all my dreams, reached what I wanted to reach: my goal was to become a complete player as possible.
“Now I’m enjoying my football. People know what they will get from me.”
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