Manchester United manager Sir Alex Ferguson believes any one of six teams could win the Premier League this season.
Ferguson is not prepared to write off any of the traditional big four, even though Arsenal have endured a miserable summer, with question marks remaining over the futures of star men Cesc Fabregas and Samir Nasri, and Liverpool are without a championship since 1990.
And, with Manchester City preparing to make a concerted challenge on top spot and Ferguson believing Tottenham will benefit from being out of the Champions League, the United boss feels it will be a tougher title race than ever this season.
''We used to talk about a top four, with ourselves, Arsenal, Chelsea and Liverpool,'' he said. ''You can't say that any more. Manchester City have definitely come into the frame. They have a buying power better than the rest of us.
''Maybe having the run in the European Cup just stretched Tottenham too much last season and they ended up being out of the top four. But you look at those teams and say any one of them could win the league.''
And Ferguson believes United's tour of the USA will be part of a vital preparation for what lies ahead.
''We know it is going to be such a big challenge again this season,'' said the Scot. ''It never changes. It is not an easy league to win. But we have experience of winning it. That helps.''