Despite reaching their third Champions League Final in four years in 2011, Manchester United's last success in Europe's top club competition remains their dramatic penalty shoot-out victory over Chelsea in 2008.
With the acquisition of Arsenal's goal-machine Robin van Persie last summer, many tipped United to lay siege to all four of the competitions they contested, and while talk of a potential treble was always going to be illusory, the smart money would have been on yet another record breaking year for the Red Devils.
Yet following their controversial defeat to Jose Mourinho's Real Madrid in the last-16 last month, Sir Alex Ferguson will have to wait yet another year before getting his hands on the famous trophy "with the big ears".
Here, we take a look at 5 potential transfer targets who could help crown United Kings of Europe once more in 2014.
Manchester United have been tracking Borussia Dortmund's impressive centre-back, Mats Hummels, since last year, and in October, the German international gave Alex Ferguson a boost by claiming he intends to leave the Bundesliga "one day" and refused to rule out a move abroad.
The 24-year-old has been an integral cog in Jurgen Klopp's Dortmund machine over the course of the last few seasons, helping Die Schwarzgelben to back-to-back German championships in 2011 and 2012. He has also put in numerous solid defensive displays throughout their run in this year's Champions League.
United do need a new centre-back. Nemanja Vidic has had another prolonged spell on the sidelines this season and missed all of October and November's fixtures through injury, and there are also concerns over Rio Ferdinand's fitness.
Though the Reds do have numerous young fledglings coming through the ranks in Phil Jones and Chris Smalling, there is a feeling that they need one more world-class centre-back.
Along with the centre-back position, left-back is another area of concern for Sir Alex Ferguson's side. Patrice Evra will be 32 in May, and the full-back has enjoyed a less than stellar campaign this season.
There are many who say he is no longer the player he once was, and his positioning has at times been called into question. United have had some particularly hairy moments at the back this season, particularly in their crazy 4-3 win over Reading in December, and have certainly conceded more goals than they will have cared for this term.
Has time run out for United's veteran left-back? Is it time for a change? Alexander Buttner has looked capable in the occasional outing for the Red Devils, but can he replace Evra? That remains to be seen.
One of the best left-backs in the world today is Everton's Leighton Baines. United were said to be tracking the Everton star back in December and were prepared to table an offer for the £15 million-rated star.
Baines has many of Evra's qualities. He is a goal-scoring wing-back not afraid to venture forward in attack and is also a tough tackler of the ball. He was most impressive for England in their recent World Cup qualifiers and has been tipped to oust Ashley Cole.
The Colombian winger is regarded as one of the finest young talents in European football at present. The 21-year-old Porto star has scored eight times in 21 appearances so far this season.
United look resigned to losing Nani in the summer, who has long been unsettled at Old Trafford, and need a new winger. They are hoping to use the Portuguese' flier and Anderson as bargaining chips as part of any move for the star, who is valued at a hefty £36 million.
His transfer value has skyrocketed from £24 million last year after a number of brilliant performances, which goes to show just how highly rated he is.
His dribbling, speed, creativity, ball control and powerful shots have seen him compared to Cristiano Ronaldo—even to the point where he is considered his South American counterpart, which is the ultimate compliment.
United have been tracking Celtic's powerful defensive midfielder since January, and Sir Alex Ferguson watched the Kenyan in action in a 4-0 win over Dundee United late that month, when Wanyama got on the scoresheet.
He also shone against Barcelona in the Scottish side's famous Champions League win in the group stages and was an influential figure throughout their run into the last 16. Celtic have been trying desperately to tie him down to a new contract, but with no agreement on the horizon, United and a number of other leading European clubs are preparing to swoop when the transfer window reopens this summer.
The Red Devils have lacked an authoritative figure in the centre of their midfield ever since the departure of Roy Keane, whom Ferguson never managed to replace. Imbued with strength and aerial prowess and capable of playing at centre-back, Wanyama could be just the player United need right now.
Robert Lewandowski has been in fine form for Borussia Dortmund this season and is one of Europe's most potent strikers at present. He has netted 27 times in 37 appearances for Jurgen Klopp's side and has been one of their star performers.
Ferguson is a keen admirer of the Polish marksman and was said to be weighing up an offer back in December. When the forward revealed he would not be renewing his contract with the club, the Reds appeared to be in pole position for his signature.
In March, Bayern Munich emerged as candidates for his services and appeared to have stolen a march on their rivals.
Many say United don't need another striker. After all, they have an embarrassment of riches in that department with Wayne Rooney, Robin van Persie, Danny Welbeck and Javier Hernandez Balcazar all vying for places. However, Welbeck still needs room to develop, while RVP will be 30 in August.
There is also still uncertainty over the long-term future of Rooney, and Hernandez Balcazar has been used only sparingly this term.
Perhaps United could make room to accommodate Lewandowski after all?