The man to suffer is often Rooney with the 23-year-old asked to play out of position in a role which sometimes nullifies his attacking threat - two goals in the last seven games - allowing for Cristiano Ronaldo to play through the middle.
The system worked to great effect against Arsenal at the Emirates in the second-leg of the Champions League semi-final and Ferguson believes that Rooney can be even more dangerous cutting in from the flank rather than playing as a central striker.
"When forwards attack from wide to inside they are far more dangerous," he told The Guardian.
"It's funny when I see centre-forwards starting off in the middle against their markers and then going away from goal.
"Strikers going inside are far more dangerous, I think. When (Thierry) Henry played as a striker, and sometimes, when Wayne does they try to escape and create space by drifting from the centre to wide positions, when that actually makes them less dangerous."
Does he have a point that strikers in this 433 thing are more dangerous out wide? Should the team have 3 striker starting every game? So for us it would be Torres, Kuyt(!), and striker x?
I thought that having 3 strikers on the pitch would unbalance the team for most games, but this blokes has just won the league again so knows a lot more than me obv. Is Rafa planning on playing 3 strikers next season?
Henry was lethal out wide left and coming in, on a side note.