It may not have turned into a full blown crisis but Manchester United are definitely beginning to wobble. According to Sir Alex Ferguson, things started to go wrong at the end of February when their incredible run of clean sheets came to an end against Blackburn. Since then they have suffered defeats to Liverpool and Fulham and against Porto looked thoroughly unimpressive. The midfield three of Darren Fletcher, Michael Carrick, and Paul Scholes left the defence horribly exposed; allowing Porto's attacking players to cause havoc. United will almost certainly have to beat Porto in Portugal, something no English side has managed to do yet, but with so much talent at Ferguson's disposal you wouldn't bet against them.