Arsenal make the trip to the North-West having put together a 12-match unbeaten streak in the top flight, with their latest victory coming over Tottenham Hotspur on Sunday afternoon.
United have recorded 12 points from a possible 21 since Jose Mourinho was reportedly on the brink of the sack but while that appears to be a respectable return on paper, it is the team's performances which remain the biggest issue.
Credit should be given to Mourinho and his players for the number of points which they are claiming from losing positions, with five coming from their last six outings in the Premier League and a famous triumph being achieved at Juventus in the Champions League.
However, the club's hierarchy and supporters do not want to be content with praising comebacks, and Mourinho needs to get United playing with pace and tempo if they are to receive any prolonged praise from behind the scenes and in the stands.
Few players have shown that they are prepared to meet those demands, nor does it appear that Mourinho feels the need to adapt his own methods, but Wednesday's showdown with Arsenal could be just the occasion for United to deliver.
Arsenal holding such a sizable lead over United at this stage of the season felt unrealistic in the summer, but the switch in trajectory of both clubs has only led to the stakes increasing ahead of the meeting at Old Trafford.
Defeat for United would leave Mourinho with just two wins from seven Premier League matches and, more importantly, lead to the club being at least nine points behind the top four.
Mourinho has already been able to see off persistent speculation about his position, but a further setback against Arsenal would only highlight the contrasting directions in which the two clubs appear to be heading.
The Portuguese will feel encouraged that Romelu Lukaku was able to end his lengthy goal drought at the weekend, but it is going to take a united effort for the club to remain contenders for a place in next season's Champions League.
Recent form: DWWLDD
Recent form (all competitions): WWLDWD
Unai Emery came in for criticism when Arsenal were outplayed and held to a draw by Wolverhampton Wanderers at the Emirates Stadium last month, and it represented the Gunners' third successive stalemate in the top flight.
However, Emery will feel that he deserves equal praise for his willingness to change the team's formation, with the switch in tactics leading to impressive wins at Bournemouth and against Spurs.
There will be concern over Arsenal's inability to hold a lead at half time, but Emery is only discovering that he will not have any issues with the character of his team heading into an important period of the season.
Arsenal were far from perfect against their neighbours on Sunday afternoon, but fighting back from a 2-1 deficit to record a convincing win created a spectacle and atmosphere which have not been experienced at their home ground in some time.
The second-half impact of Aaron Ramsey will only raise more questions over why he is being allowed to depart the club on a free transfer in the summer, but Emery will prefer to focus on how Pierre-Emerick Aubameyang is establishing himself as one of the best strikers in the Premier League.
The Gabon international now has 10 goals and two assists from just 1037 minutes of top-flight football this season, and maintaining that kind of form would go a long way to Arsenal earning a return to the Champions League.
Arsenal still have some way to go to be considered as challengers for the league title, but the displays of Aubameyang in the final third and Lucas Torreira in the middle of the park have only led to expectations going up several levels.
Emery will be aware that United, Liverpool and Chelsea are all to come over the next seven weeks but for now at least, there is every confidence that the Spaniard is beginning to put together something special.
Recent form: WDDDWW
Recent form (all competitions): DDDWWW
Mesut Ozil could be handed a place on the Arsenal bench if he has recovered from the back spasm which kept him out of the game against Spurs.
Mourinho will be forced into at least one change with Ashley Young having to sit out the fixture due to a one-game suspension.
That could lead to a start for Diogo Dalot at right-back, although there could be a shortage of options elsewhere in defence with Chris Smalling, Eric Bailly and Phil Jones all doubts and Victor Lindelof still sidelined.
Marcus Rashford contributed two assists at St Mary's, but Mourinho may choose to keep the attacker among his replacements with the England international said to be suffered from fatigue at the weekend.
Manchester United possible starting lineup:
De Gea; Dalot, Smalling, Jones, Shaw; Matic, Herrera; Lingard, Pogba, Martial; Lukaku
Arsenal possible starting lineup:
Leno; Sokratis, Mustafi, Holding; Bellerin, Torreira, Guendouzi, Kolasinac; Ramsey, Aubameyang, Lacazette
Head To Head
Wednesday's encounter will represent the 228th competitive clash between the two clubs, with United having won 98 times in comparison to 82 wins for Arsenal.
Neither team has put together three successive wins in this fixture since United did between August 2011 and November 2012, but Mourinho's team can achieve that this week.
Arsenal have not won at Old Trafford in the Premier League since 2006, although they did prevail in an FA Cup tie as recently as 2015.
We say: Manchester United 2-2 Arsenal
Manchester United have struggled at Old Trafford this season, but the visit of Arsenal could be the match to spark them into action. Arsenal are full of confidence ahead of this contest but with United having more preparation time for this fixture, we feel that an entertaining draw is the most likely result.