After eight years at Old Trafford, Nemanja Vidic, the Manchester United club captain, will become the first high-profile casulty of David Moyes' reign by leaving the club at the end of the season.
Vidic has won 15 major honours including five league titles and has been a pivotal member of United's continued success both domestically and in Europe.
Having signed Juan Mata in the January transfer window, United are clearly willing to invest in replacing the colossus but Moyes faces a tough ask identifying a candidate for the role.
IBTimes UK looks at five candidates to replace the United skipper.
Andrea Ranocchia Age: 25 Club: Inter Milan
Profile: The 6 ft 5 in Italian international would be ideal fit in the centre of the United defence. With the power and presence alone to replace the role of Vidic, Ranocchia has struck the fear of life into attackers in Serie A.
Complications: With Inter expected to offload contract rebel Ranocchia this summer, a year ahead of his current contract expiring in order to recoup some of the €19m invested in him in 2011, United could be among the teams interested. Juventus and AC Milan will be among their rivals.
Benedikt Howedes Age:25 Club: Schalke 04
Profile: Among the most consistent defenders in Europe, Howedes has been hugely influential in Schalke's recent improvement. The Schalke club captain is the and heart and soul of the Bundesliga club, with his sense of positioning among the best on the continent.
Complications: Having signed a new four-year deal until 2017, United would have to break the bank for the World Cup bound German international. Any return to the Champions league and retention of Julian Draxler would further cement his future.
Leonardo Bonucci Age: 26 Club: Juventus
Profile: More in the mould of Rio Ferdinand than Vidic but with the potential to lead the United defence for the remainder of the decade. Now a regular for Juventus after sporadic appearances in his first years at the club.
Complications: Another who has committed himself long term having signed deal until 2017 with the Serie A champions. The added complexity comes in the form of other suitors for his services, with Arsenal, Monaco and Manchester City all reportedly keeping tabs on the Italian.
Mats Hummels Age: 25 Club: Borussia Dortmund
Profile: A graduate from the Bayern Munich academy but now thriving at rivals Dortmund. Comparisons with Franz Beckenbauer might be somewhat farfetched but there remains no doubt Hummels is among Europe's finest centre-backs.
Complications: As Barcelona discovered last summer, Dortmund's valuation of Hummels, not least the three and a half years remaining on his contract makes any attempt to prise him away difficult. As shown with Robert Lewandowski, the club would sooner see his deal expire than sell.
Eliaquim Mangala Age: 22 Club: FC Porto
Profile: A physical presence to match Vidic and then some. Mangala is spearheading a Porto back four which is among the best in Primeira Liga this season. At just 22 he represents a player to build a team around and possesses pace to burn and assurance in possession.
Complications: Manchester City came close to signing the France international in the summer meaning that United are not only on the back foot, but face a bidding war with their big spending rivals. Porto are however willing to let the player leave.