United head to London off the back off a jarring 1-0 defeat to Brighton & Hove Albion, but could require just a single point from the match to wrap up second place.
West Ham United
After weeks of torment and varying degrees of nail-biting, West Ham fans can now rest assured that they are guaranteed another season in the top flight of English football.
The club's fortunes looked bleak just a few months ago following a tumultuous defeat to Burnley that incited waves of fan protests, but Moyes has since been able to steady the ship in just enough time to stave off relegation.
The Hammers guaranteed themselves survival last weekend, when they went to Leicester City and pulled off an impressive 2-0 victory at the King Power Stadium, courtesy of goals from Joao Mario and Mark Noble.
Moyes will now be hoping to look on towards the summer as he plans to build this team in his own image after producing a decent firefighting job since the departure of Slaven Bilic.
Some sections of the club's support have been vocal in their criticism of the manager since his arrival, although Moyes has arguably done an impressive job given the Premier League staples of Stoke City and West Bromwich Albion that have recently fallen around him.
The Hammers welcome United to Old Trafford aiming to win their first back-to-back league games in the division since 2017, and that statistic perhaps indicates the sort of trouble that the club have at times found themselves in this term.
West Ham fans will be delighted with the return that Marko Arnautovic has shown since his arrival. The Austrian came in for some criticism at points during his early Hammers days, but the forward is now the club's leading scorer this term, having bagged 10 league goals.
With the pressure arguably off Moyes and his charges, West Ham have the opportunity to go out and test a United side that have once again come in for stick after another lacklustre showing against a side from the bottom half of the table.
Recent form: WDDLLW
Mourinho's United enter their final away game of the campaign requiring just a single point to ensure a second-placed finish. Should Tottenham Hotspur not win on Wednesday, the Red Devils will take second place regardless.
As has been the case for much of the campaign, United in 2018 have offered glimmers of brilliance laced with frustrating inconsistencies. The latest of those came to rear its head last weekend against Brighton & Hove Albion, who beat United 1-0 at the Amex to secure their own safety in the Premier League.
Mourinho was evidently peeved after the defeat and hinted that the performance highlighted exactly why he has not given his fringe players too many chances this season. It was not only United's squad players at fault, however, with another perplexing showing from Paul Pogba raising eyebrows once again.
The Red Devils were left bamboozled by Manchester City this term, while their European fortunes will likely scar Mourinho's project for many months to come following a dismal exit at the hands of Sevilla in the last 16 of the tournament.
Mourinho does still have a chance for silverware, however, leaving the coach desperate to lead his side into the FA Cup final off the back of some positive form in the latter stages of the campaign.
United could lose two league games on the bounce for the first time in the best part of a year, but Mourinho will be hoping that his side can bounce back straight away against the Hammers to confirm second place before the final day of the season.
Mourinho himself goes into the contest with a remarkable record against Moyes - the Portuguese coach is unbeaten in 10 Premier League matches against sides managed by the Scot.
United fans will be eager for their side to rewrite some average away form in the closing stages of the campaign in recent years. The Red Devils have not won their final away trip of a season since beating Sunderland in 2011-12.
Recent form: WWLWWL
Recent form (all competitions): WLWWWL
The Hammers are likely to be without former United frontman Javier Hernandez, who is suffering from a knee issue, while Michail Antonio, Sam Byram, Winston Reid and Pedro Obiang remain long-term absences.
Moyes is expected to lead with the same side that beat Leicester last weekend, leaving Arnautovic to be supported by both Mario and Manuel Lanzini.
As for the visitors, United will be without top scorer Romelu Lukaku for the final two games of the term, although he should return for the club's FA Cup final showdown with Chelsea.
Marouane Fellaini is out injured for the trip, but Alexis Sanchez should make a comeback having missed the Brighton game. Marcus Rashford is expected to keep his place up top despite struggling against the Seagulls.
West Ham United possible starting lineup:
Adrian; Rice, Ogbonna, Cresswell; Zabaleta, Noble, Kouyate, Musuaku; Lanzini, Mario, Arnautovic
Manchester United possible starting lineup:
De Gea; Valencia, Bailly, Smalling, Shaw; Herrera, Matic, Pogba; Sanchez, Rashford, Lingard
Head To Head
West Ham have only managed a total of five wins against United in 43 Premier League meetings. The Hammers last beat United in 2016 during their final fixture to be held at Upton Park.
United won the reverse of this fixture 4-0 on the opening day of the season at Old Trafford, Lukaku bagging a brace, while Anthony Martial and Pogba also got themselves on the scoresheet.
When visiting West Ham, United have only previously failed to score an away goal in two games against the Hammers. Those blanks came in a draw in 1998 followed by a 1-0 loss a few years later in 2006.
We say: West Ham United 1-2 Manchester United
The Red Devils will be playing to secure a second-place finish and that should be more than enough motivation for Mourinho's men, who will also be spurred on by last week's poor showing at Brighton.
United are the only club who have not drawn a Premier League fixture this year and that does not look likely to change as the players find themselves competing for spots in Mourinho's FA Cup final side.
Proceedings could go one of two ways for the Hammers - they either welcome United buoyed by the pressure now being off, or they find themselves with their feet up with Premier League safety already secured.