Rio Ferdinand has launched a scathing attack on Manchester United for allowing homegrown striker Danny Welbeck to leave Old Trafford for Arsenal back in 2014, branding the decision “an absolute balls-up”. The former United captain, who shared the dressing room with Welbeck for several seasons, believes the club made a huge mistake by sanctioning the £16 million ($21m) transfer, a move he insists never should have been allowed to happen.