With the two teams entering this game in highly contrasting form, anything but a win for Ole Gunnar Solskjaer's men would be seen as a huge disappointment – even more so when three points this evening could see Manchester United go fifth with a game in hand on the above teams.
But what should United fans be looking out for tonight?
United's approach to the opening period:
Conceding early goals has become a regularity for United in recent weeks and it is important that they don't succumb to the same opening tonight.
United have had to come from a goal down to win every away game this season – a sign that United are resilient and have great character. However, if you keep going goals down in games, the time will come when you aren't able to bring it back.
And it would be disastrous for this to be the case tonight.
Therefore, it will be interesting to see how the away side begin the game. United fans may be expecting their side to be quick out the blocks tonight and go for a killer goal or two in the opening period – this could easily be the case.
But after performances in recent weeks, United may begin the game with a pragmatic approach to see how the game pans out. Ole's reds have the quality to see a match out against a team of Sheffield United's quality, but going a goal or 2 down gives the game an entirely different complexion.
Perhaps a pragmatic approach would best suit United tonight, but it is not in the away side's nature against the so called "lesser" teams.
Can United expose Chris Wilder's Blades?
For the vast majority of last season, Sheffield United were an extremely strong outfit; although they didn't score an abundance of goals, as a team they were robust and resolute and teams struggled to break them down.
This was shown in last season's edition of tonight's fixture.
Although Ole's men scored 3 goals at Bramall Lane last season, it was in a short 7 minute spell – the reds created nothing for the majority of the match and could count themselves lucky to come away with a point.
This would be far from the case tonight. Sheffield United have been leaking goals all season – 21 to be exact.
And although Manchester United have had defensive problems themselves, tonight's home side have only managed to convert 5 chances this season.
If Ole's reds perform like they can, Chris Wilder's back line will be in for a torrid evening.
With pace and ability consistent throughout Manchester United's attacking players, and having scored 19 goals this season, the away side will be looking to bring all three points back to Manchester.
Will Paul Pogba play?
This question seems to be on United fans' minds every week. Will he play? Won't he play? Will he do this? Will he do that?
These are uncertain times for Paul Pogba – and it is far from the first time that this can be said.
With underwhelming performances but moments of brilliance, it is hard to predict wether Pogba will be selected by Solskjaer.
If Pogba doesn't start and Manchester United are trailing in the game at half time or in the second period, it is highly likely Pogba will be brought on – something that has become somewhat of a tradition for United this season.
But wether he starts or not is the real question. Nobody seems to know. It sometimes seems like Solskjaer doesn't know if he should play Pogba or not.
The midfielder's future is unclear, particularly after last weeks comments by agent Mino Raiola – but a start for Pogba tonight alongside a strong performance could maybe, just maybe, kickstart Pogba's season.