"In the Premier League, there are many [rivals], which are top six let's say. They will give a hard time for everybody.
"Like last season, Chelsea was the best team, they won. You'll still have Chelsea, you have Liverpool ... I think Everton are not to be underestimated, because they have a great coach and they are investing a lot to win.
"And obviously you have Arsenal, [Manchester] City. So, I think it will look like last year, but this year the Red Devils will be on top."
United initially seemed reluctant to renew Ibrahimovic's contract, given he earns about£350,000 ($NZ622,200) a week and would not play for so long. It was also the first major physical breakdown of his career, raising fears he would not be the same player when he did return.
However, having decided to carry out his rehabilitation at United's Carrington base, Ibrahimovic has stunned medical staff with the speed of his recovery, and a player who scored 28 goals in his first season in England sees no reason why he will not return as strong and as mobile as he was before the injury.
"In the beginning, when [the injury] happened, it was something new for me, because it was a big injury," Ibrahimovic told ESPN FC. "But mentally I am strong.
"I work hard, I haven't had a day off since the injury. I want to be the one I was and even better."
Asked about Lukaku, Ibra added: "Yeah, I'm happy he came. I think the team is much stronger this season, although we lost [Wayne] Rooney, a legend.
"Signing Lukaku makes us even stronger, because he has different qualities from me as a striker and from [Marcus] Rashford as a striker. He is a powerful guy and he brings extra qualities in a game."