There is talk that Manchester United's failure in the transfer market prompted Sir Alex Ferguson's retirement.

The Daily Star Sunday says Fergie had a dream team in mind for next season, including the shock return of Cristiano Ronaldo from Real Madrid - and the arrival of Gareth Bale from Tottenham.

There is a theory in the game among his managerial rivals that the realisation that those deals weren't going to happen was, at the very least, a contributory factor in his decision to retire.

In a 4-2-3-1 formation, Fergie was dreaming up a sensational attack that would have seen Robin van Persie as the spearhead, with the three behind him being Ronaldo, Shinji Kagawa and either Wayne Rooney or Bale.

Had that come off, the United chief would never have had a better chance of winning his third Champions League title next season.

But signing both Ronaldo and Bale would have cost United around £135m.