Falcao made 29 appearances and scored four goals during nine months at Old Trafford.
United, who had roped in Angel di Maria, Ander Herrera, Luke Shaw, Marcos Rojo and Daley Blind ended the summer 17 points adrift of winners Chelsea
Manchester United need just a point to secure Champions League qualification, although fifth-placed Liverpool are six points behind and with a far inferior goal difference.
Attacking trios are nothing new in football. Some of the greatest teams in the history of the beautiful game had a trio leading from the front.
Chelsea face a resurgent Manchester United in what could be the the first big hurdle in its way to English Premier League title.
Arsenal FC and Liverpool FC are face to face in the crucial game of Barclays premier league.
Martin Skrtel banned for three matches after failing to overturn a charge for stamping on the leg of Man United goalkeeper David de Gea