8) Anderson
How Anderson spent eight seasons at Old Trafford is puzzling. His Manchester United career consisted of long periods of average midfield play mixed with the occasional flash of brilliance. Despite coming in as a hot young prospect the Brazilian never fulfilled his potential.
He got several opportunities to prove his worth under Sir Alex Ferguson making over 100 appearances in the league. He won the title wth United four times but only scored five 5 goals.
After Ferguson stepped down his game time diminished even further under David Moyes. He was eventually loaned out in 2013/14 to Fiorentina but had an unsuccessful spell there as well. The player finally left the club in 2015 and currently plays for Internacional in Portugal.