David Moyes' first months in charge have been compounded by United's incredibly poor home form in the Premier League, and a shocking third-round knockout in the FA Cup by Swansea City.
After a 2-1 defeat in the first leg at Sunderland, Moyes knows that his only realistic chance of silverware, to add to the Community Shield, is the League Cup.
Sunderland, meanwhile, will still earmark Premier League survival as their priority, but a trip to Wembley to face Manchester City would do wonders for confidence in Gus Poyet's squad.
Moyes has called on his team to win the tie for the fans, who have shown him and his stricken team tremendous support over the past few weeks:
Black Cats' big chance
Sunderland have only defeated United twice in 25 matches, per The Independent, but both of these victories have come in the League Cup.
However, with The Black Cats in a rich vein of form, and United stuttering continually on their own patch, Poyet's team will see this as an excellent opportunity to reach one of English football's showcase finals.
In Adam Johnson, the North East team have one of the Premier League's most in-form and influential players. Johnson has scored or assisted in nine of Sunderland's last 11 goals, per BBC Sport, as the player looks to increase his chances of going to this summer's World Cup.
Poyet has stressed his team must put in the "compete performance" to win at Old Trafford for the first time since 1968, per BBC Sport. In an interview with the club's website, per Sky Sports, he said:
It's a great opportunity to put ourselves in a final but we've only done part of the job. You never know how much - whether 50% or not - but definitely a part. You don't get to a semi-final every year - sometimes not even in 10 years.
We must go there and try to make sure we finish the job and put ourselves in the final. We need a complete game - we must defend well, be strong and be good on the ball - much better than the other day [against Southampton].
A Wembley trip would define Poyet's first season in charge, after taking over the club from the heavily criticised Paolo Di Canio.
How Moyes can get it right
Moyes has shown no sign of fear in his team selections, putting his faith in the youth of Adnan Januzaj and company, during an incredible run of injuries to the squad.
Tactically, Moyes has been conservative, using similar formations to that of his predecessor, Sir Alex Ferguson. However, lately the Scotsman has moved away from 4-4-2, adapting to a more fluid 4-2-3-1/4-3-3 at times, and trying to utilise his talented teenage Belgian off the striker.
It is likely that Phil Jones will return to his preferred centre-back role to partner Jonny Evans, with Nemanja Vidic suspended after his red card at Chelsea. This will also see Darren Fletcher return to the first team, to partner Michael Carrick in Jones' midfield absence.
The Scottish international has looked impressive since his return to fitness, after illness kept him out for a year.
Alternatively, United could also give a start to Tom Cleverley, who has struggled for form in recent weeks. The England international said to Sky Sports, per The Independent:
We have had to rethink our targets for the year but this club is about winning trophies. We are still well in the Champions League and are in the semi-final of the cup. We have to shoot ourselves up the league, then hopefully we can end the season positively.
With United needing goals to progress, and with Wayne Rooney and Robin van Persie not close enough to full fitness, Moyes is likely to opt for a combined attack of Danny Welbeck and Chicharito.
Welbeck is United's most in-form player, with eight goals from his 16 league matches this season, per Squawka. He has pulled United through a rough patch, despite the team still struggling to win games.
Welbeck has proven that he can be a regular goalscorer for Moyes' team, but this will only happen when he is playing the role of striker. His lack of goals last season was mainly due to his wider starting position.
With Patrice Evra coming off the field early against Chelsea, it is likely that Alexander Buttner will make a rare start, having the opportunity to impress his manager before the arrival of any new left-backs to the club.
Once again. Shinji Kagawa appears to have fallen down the pecking order in the manager's plans, but with Rooney still out, the Scotsman might turn to his Japanese international to provide some flair.
If United perform anywhere near the standard that they can, they will progress to the final. However, a defeat will see Moyes' team morale hit a new low, with only days left in the transfer window to address the obvious playing staff issues.
Victory will give United fans something to look forward to. For the club has always relished the tag of "underdogs," which they surely would be, if they reach Wembley.
Score: Manchester United 2 Sunderland 0