Arsenal will likely be focused on next week's second-leg Europa League semi-final clash with Atletico Madrid, but Wenger will also be yearning for a victory as he prepares to say goodbye to a ground that has hosted many a famous battle involving the Frenchman.
Much of the emotional sentiment surrounding Wenger's last Arsenal visit to Old Trafford will be linked to his battles with Sir Alex Ferguson, but it is worth noting that the Frenchman has also had notable run-ins with Mourinho.
The pair's rivalry hit a peak in 2014 when then-Chelsea manager Mourinho labelled Wenger a "specialist in failure", a comment that preceded an infamous tussle on the touchline in the winter of the same year.
The pair have met 18 times prior to this fixture; Mourinho found himself unbeaten in the first 13 meetings, but the Portuguese coach has since lost two of the last five when facing Wenger. Mourinho has never suffered defeat as a home manager against the Frenchman, though.
Old Trafford is likely to show Wenger respect when he visits for the last time as a Gunners boss, but that will not stop Mourinho from wanting to strengthen United's grip on second place. Mourinho will be wanting to build on the club's record of winning their last four league fixtures against sides in the top six.
Alongside Wenger's departure comes another narrative in which Alexis Sanchez will be facing his former club, having left the Gunners in January. The Chilean has been far from his best during the early stages of his United career, although his showing against Tottenham Hotspur in the FA Cup semi-final perhaps hinted at better things to come from the 29-year-old.
Mourinho's charges are aiming to bounce back from a shock defeat to West Bromwich Albion at Old Trafford, which ultimately handed Manchester City the title with five games to spare. Should United lose out to Arsenal, the club will have suffered two defeats on the bounce at home for the first time since March 2014 under the tenure of David Moyes.
United are now 10 league games unbeaten at Old Trafford against the Gunners, having won seven and drawn three of those meetings. The run is the second-longest the club have shared since an impressive stretch of 17 games during the early 1960s.
One man who will likely be crucial for the Red Devils is stopper David de Gea, who shone between the sticks when United beat Arsenal 3-1 at the Emirates earlier in the season. The Spaniard made 14 saves in that game, which represents the most made by any keeper in a fixture this term.
Recent form: WWWWLW
Recent form (all competitions): WWWLWW
Wenger heads to Old Trafford on Sunday as the Frenchman prepares to feature at the Theatre of Dreams for the final time as manager of the Gunners.
The ground has played host to endless battles between the Frenchman and long-time footballing rival Ferguson. There are boundless memories of historic clashes at the stadium, including the Battle of the Buffet, Martin Keown and Ruud van Nistelrooy clashing and the Gunners losing 8-2 to Ferguson's side in 2011.
None of those games will evoke the same emotional reactions as the climactic contest in 2002, though, as the Gunners claimed the title at Old Trafford on their way to a historic double under Wenger's stewardship.
Off the back of those incidents, Wenger now heads to Old Trafford to face a more contemporary rival in Mourinho, although the Frenchman's focus might just have shifted from a renowned derby clash to Arsenal's exploits in the Europa League.
Wenger's last game at Old Trafford for the Gunners might be overshadowed given how important getting beyond Atletico in the Europa semis will be for the club next season. Lifting the trophy would also provide the French coach with a cup-winning send-off.
Arsenal missed a huge chance on Thursday evening to gain a lead against Atletico at the Emirates, as Wenger's side could only draw 1-1 with Diego Simeone's charges, who played the best part of 80 minutes with 10 men after the dismissal of Sime Vrsaljko.
A calamitous defensive error from Laurent Koscielny arguably handed Antoine Griezmann the chance to equalise, after Alexandre Lacazette had initially headed Arsenal into the lead, leaving Madrid with a crucial away goal heading into the return leg in the Spanish capital next week.
Europa glory remains Arsenal's only realistic route towards Champions League qualification next term, potentially leaving Wenger to turn his gaze away from United as he prepares to find a way to get beyond Atletico at the Wanda Metropolitano.
Recent form: LWWWLW
Recent form (all competitions): WWDLWD
Antonio Valencia should start for United despite picking up a muscle problem when facing Spurs in the FA Cup last weekend.
Mourinho is expected to lead with Romelu Lukaku in attack, with Jesse Lingard and Sanchez providing creative support. The Portuguese coach could opt to continue with Paul Pogba, Ander Herrera and Nemanja Matic in a three-man midfield.
Lacazette has scored four goals in his last four appearances, but he will likely be rested for the Europa as Pierre-Emerick Aubameyang returns after being cup tied on Thursday.
Henrikh Mkhitaryan is struggling with a knee injury and he will likely feature against Atletico in the second leg instead of being risked at Old Trafford.
Manchester United possible starting lineup:
De Gea; Valencia, Smalling, Jones, Young; Matic, Herrera, Pogba; Sanchez, Lingard, Lukaku
Arsenal possible starting lineup:
Cech; Chambers, Mustafi, Holding, Kolasinac; Willock, Xhaka; Welbeck, Iwobi, Nelson; Aubameyang
Head To Head
United are in the middle of an impressive home run against the Gunners, having been unbeaten in 10 league games stretching back to September 2006.
Mourinho won 3-1 at the Emirates earlier in the season in a bizarre game in which Arsenal passed up a number of chances to put United to bed. The Manchester club have not bagged a league double against Arsenal since the 2011-12 season.
The last six fixtures between the sides have been played out in the Premier League, with the points being shared equally across those games, each side winning two and drawing two.
We say: Manchester United 3-1 Arsenal
Mourinho will not want to show any sentimentality as he aims for a top-two finish in the league and the chance to gain a league double over Wenger with a victory at Old Trafford.
Wenger arguably has his focus elsewhere with the Europa and he could rest a number of key players for the game. The Gunners have already lost nine Premier League away matches this season and have just 57 points with four games to play. Wenger's lowest points record for the club was 67 back in 2005-06.
The footballing community is quite rightly yearning for another standout match between the legendary Premier League rivals, but Arsenal's preoccupations in Europe might give United a slightly more navigable game on Sunday.