Mourinho believes he has a squad capable of winning the Premier League next season but accepts that any of the title hopefuls could also easily end up fifth, with Manchester United expected to challenge again.
He said: "Last year, if you had asked me in July, I would never have said Man United would be outside the top four. This season I will tell you one will miss out and I have a big percentage of making a mistake.
"There were good teams last season and there will be better teams this season because everyone is investing.
"A few years ago you make a team to be champions and most probably you will be. Now if you make a team to be champions, you try to finish in the top four.
"Why I like the Premier League so much is that at this moment, nobody knows who is going to win the title.
"I know that we want to and I know that we can but it is the kind of competition where I can't say.
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