Terry Venables says Manchester United's owners are to blame for their Champions League failure this week.
In his column for The Sun, former Barcelona coach Venables wrote: "The manager's decision to take a chance on Wayne Rooney in Wednesday's quarter-final return with Bayern Munich is not the reason the Red Devils failed to make it to the last four of Europe's elite competition.
"But his inability to spend significantly on new signings in the last two transfer windows is.
"And for that costly call, fingers can only be pointed at the club's American owners.
"Despite receiving a world-record £80million from Real Madrid last summer for Cristiano Ronaldo, the only money they have splashed on new signings this season is £16m to Wigan for Antonio Valencia and £3m to Bordeaux for Gabriel Obertan, while Michael Owen arrived from Newcastle for nothing.
"It left Fergie going into this season with a squad containing only three experienced strikers in Rooney, Owen and Dimitar Berbatov.
"I am sure the manager - renowned for his reliance on four able frontmen in previous seasons - would have known the risks involved.
"And I am sure he would have tried to bring in another striker had he been allowed. But that never happened."