The Red Devils have closed the gap on the top four to just two points in recent weeks, but come up against a Watford side buoyed by back-to-back wins.
Considering Manchester United are currently on their longest unbeaten run since the days of Sir Alex Ferguson, and indeed the longest ongoing run in Europe's top five leagues, it may be a source of frustration for manager Jose Mourinho that his side have still not moved from their position in sixth.
It is a position United have been stuck in since November 6, but while there has been no progress made in terms of their placing in the Premier League table during that time, there have been encouraging signs in their push for a top-four spot.
Indeed, United could end a gameweek in the Champions League places for the first time since September should other results go their way this weekend, while victory over Watford is guaranteed to lift them up to fifth for a few hours at least, with Liverpool not in action until the late kickoff.
Representatives from the club may not have publicly admitted it, but a 14-point gap to leaders Chelsea all but rules them out of the title race at this stage of the season, so the success of the campaign now rests on their ability to break into that top four, as well as their cup exploits.
United return to Europa League action next week with the first leg of their last-32 clash against Saint-Etienne, after which they face Blackburn Rovers in the FA Cup, Saint-Etienne again in Europe and Southampton in the final of the EFL Cup.
Indeed, with the current schedule United will not be back in Premier League action until the visit of Bournemouth on March 4, which only adds to the importance of picking up three points this weekend in order to limit any damage done during their absence from the top flight.
A couple of trophies and a top-four finish would have to go down as a successful debut season for Mourinho considering how the campaign has panned out so far, but it is the latter which is surely the priority considering the club's reported ambition to bring in more high-profile players next summer.
United have not been beaten in 18 home matches across all competitions, a run which stretches back to September, but in the Premier League they have actually been stronger on the road. The likes of Burnley and West Bromwich Albion both have better records in front of their own fans so far this term, with United having drawn more games than they have won at Old Trafford.
The team's most recent outing here ended in a 0-0 draw with relegation-threatened Hull City and, while they bounced back from that with a comfortable 3-0 triumph over Leicester City at the King Power Stadium last time out, Mourinho will know that his side can ill afford another home slip-up this weekend.
Recent form: WWDDDW
Recent form (all competitions): DDLWDW
Trips to Old Trafford have brought Watford very little joy in the past, but the Hornets will arrive in Manchester full of confidence this weekend for a number of different reasons.
Walter Mazzarri's side have already got one over on United this season, winning 3-1 in the reverse fixture back in September, and another triumph on Saturday would see them become just the ninth club in Premier League history to complete the double over the Red Devils.
More recently, they have strung together back-to-back victories heading into this game and have the chance to make it three in a row for only the second time in their Premier League history.
Last weekend's 2-1 win over Burnley was enough to lift the Hornets into the top half of the table, with a goal and an assist for Mbaye Niang hinting at the AC Milan loanee being a shrewd January signing for the club, but it was their win over Arsenal at the end of January which will provide the most optimism ahead of this weekend's game.
Watford stormed into a 2-0 lead in less than 15 minutes at the Emirates Stadium and held on for their first ever Premier League victory over the Gunners, ending a seven-match winless streak in the process.
Mazzarri will want to see the same attitude from his players on Saturday and, considering how slowly United have started matches in recent weeks, that could be enough to set them on their way to another famous victory.
It is worth remembering that Watford have only been back in the top flight for one-and-a-half seasons, so their mid-table positions in both campaigns so far must go down as an impressive achievement. The Hornets never looked in any danger of relegation last season and, with a 10-point gap to the bottom three as things stand, have kept themselves at a safe distance this time around too.
Victory over United would be another sign of their progress in that time, and it would also give them back-to-back away wins for the first time since December 2015 - at the Emirates and Old Trafford, no less. However, that win at Arsenal is their only victory in their last nine away games across all competitions stretching back to mid-October, and one of only three all season.
The Hornets have never before finished in the top half of the Premier League table, but victory this weekend could lift them up to ninth and closer to the top six than the bottom three, so there is plenty to be optimistic about for Mazzarri's side.
Recent form: LLDDWW
Recent form (all competitions): WDDLWW
Record Man Utd goalscorer Wayne Rooney missed the win over Leicester with illness but is expected to return to the squad this weekend.
Henrikh Mkhitaryan and Juan Mata are likely to keep their places having scored at the King Power Stadium, but Rooney could be recalled in place of Marcus Rashford after Mourinho quickly switched to a 4-2-3-1 formation against the Foxes.
Doubts remain over the fitness of Phil Jones, who also missed last weekend's game due to a foot injury, while Marcos Rojo was forced off at half time of that match and is also in a race to prove his fitness.
Mazzarri is likely to switch back to the more conservative formation used against Arsenal which will see Troy Deeney lead the line alone as he looks to score in a fourth consecutive Premier League match.
Man Utd possible starting lineup:
De Gea; Valencia, Bailly, Smalling, Blind; Herrera, Carrick, Mkhitaryan, Pogba, Mata; Ibrahimovic
Watford possible starting lineup:
Gomes; Cathcart, Kaboul, Prodl, Holebas; Janmaat, Capoue, Behrami, Cleverly, Niang; Deeney
Head To Head
Watford's victory over United at Vicarage Road in September is very much the exception to the rule in this fixture, with the Red Devils having won the previous 11 meetings between the two sides before that, stretching back to 1986.
The Hornets have never won a league match at Old Trafford, drawing two and losing seven of their previous nine meetings, including three defeats from three in the Premier League era - most recently a 1-0 loss last March when Mata scored a late winner.
United's only ever defeat to Watford on home soil came in a League Cup tie in October 1978, with Luther Blissett scoring both goals in a 2-1 win for the Hornets.
We say: Man Utd 2-1 Watford
This game could be won and lost in the opening 20 minutes or so, with United having started very slowly in recent weeks and Watford undoubtedly planning an early raid like they did at the Emirates. Should United survive that period then they should be able to grind out a win, although Watford will be full of confidence and will not make things easy for the hosts.