Every football club, no matter how successful, has their share of great signings and total duds. For every £22.8 million Luis Suarez, theres a £50 million Fernando Torres, and for every £1.5 million Ole Gunnar Solskjaer, there's a £9.5 million Albert Luque. Truth be told, some players thrive at certain clubs, under certain managers and alongside certain players. Other players are maybe not quite the player they once were when they do make the jump to another club, whilst some may be the victim of a nasty, career-changing injury. Then there are those who simply need time to adapt to a new league, a new language and a new culture. Even the very best of teams have made some absolute stinkers of signings over the years, and Manchester United are no different in that regard. Despite being a club in transition at the moment, the Red Devils are the most dominant team in Premier League history. Since the Premiership began in 1992, the Old Trafford club have won 13 League Championships, 2 Champions Leagues, 4 FA Cups, 3 League Cups, 10 Community Shields, 1 FIFA World Club Cup and 1 Intercontinental Cup. Quite the impressive collection of silverware, anyone would agree. Regardless of some of the great players who have contributed to this trophy haul, theres plenty who added nothing to the side, were merely passengers in successful teams, or were an embarrassment to the turf at the legendary Theatre of Dreams. Names like Mark Bosnich, Nani, Manucho, Phil Jones, Karel Poborsky, Roy Carroll, and dare I say the loan signing of Falcao all came under consideration but ultimately missed out. Lets look at 15 players who for one reason or another stunk up Old Trafford with their performances or lack thereof.