Erik Hamren's men are still likely to qualify for the round of 16 with a win over Belgium, though, and Ibrahimovic is desperate to extend his international career, having made the decision to retire from Sweden duty after the Euros.
"I feel good. I'm at 100 per cent. Thus far I haven't been able to play at my best level and we could have done more, including me," the striker told reporters at a press conference.
"But we still have a chance to make round of 16. We will try to improve. Every match is difficult and it won't be easy game. But we believe in ourselves. We are aware of the challenge ahead.
"There is a lot of pressure, but we're still in it and will do everything to stay in the tournament.
"I always want to win. I have a lot of responsibility, but I like this role. Being successful is all that matters. If we win we can still progress. We haven't hit the target yet, but we're going to score if we hit the target next time.
"We will get more chances against Belgium. We know we can improve, but we know what to do. We need to play a bit more like a team. We must improve, both individually and as a team.
"The Italy game was very tough. They are very strong defensively and do not give you a lot of room. They don't allow you any space.
"Give me a yard and I can make the most of it. And I think I will get more space against Belgium. We will be able to play football a bit more. There will be more chances and space."