Easily the best manager in the Premier League era of English football and one of the best in the history of the sport, Manchester United manager Sir Alex Ferguson will be retiring at the end of this season.

Ferguson has been managing clubs since 1974, when he started his career with East Sterlingshire in Scotland. He took over Manchester United in 1986, and hasn't looked back, guiding United to 13 league championships in that span and over 30 total trophies.

Sir Alex will manage the club's last two games this season, a home match with Swansea City and an away match at West Bromwich Albion, before riding off into the sunset with another English Premier League title in hand, one that United clinched earlier this season.

Whoever is faced with the daunting task of replacing Ferguson will come in with sky high expectations and zero chance of replicating the vast success that he has experienced at the helm of the Red Devils, a situation similar to coaches that have followed Phil Jackson in the NBA.

Currently, Everton manager David Moyes is being discussed as a candidate for Ferguson's replacement, despite his lack of big time success at the club in recent years even with quality talent such as American striker Landon Donovan passing through in the club's recent past.

It will be fascinating to see how United rebound from the loss of one of the greatest to ever manage a football club, and if the talent they possess is good enough to get them through what will surely be a tough transition.