The managerless Hornets are in the bottom three heading into the final round of fixtures, behind 17th-placed Aston Villa on goal difference, while Arsenal are 10th and have one eye on next weekend's FA Cup final.
Watford's destiny is no longer in their own hands following a dramatic round of midweek action that saw Villa stun Arsenal 1-0, shortly after Watford had crashed 4-0 to Manchester City.
Losing heavily to City is something that the Hornets have become accustomed to in recent times, and this latest thrashing - two days after Nigel Pearson was surprisingly dismissed - has left them requiring snookers if they are to dodge the drop.
Villa travel to West Ham United on the final day - the Hammers having secured their place in the top flight for another year on Wednesday - with a victory of any sort surely being enough to keep them up thanks to their slightly superior goal difference.
Watford have to better the Villans' result against West Ham, with goal difference possibly coming into the mix, and the Hornets are currently one goal worse off than Villa in that regard.
It is not out of the question that a third deciding factor will have to be used to separate the sides, which is goals scored - a deficit Watford, six goals worse off than Villa, are unlikely to make up.
The target for interim boss Hayden Mullins will be coming away from the Emirates Stadium with all three points, though Watford have not won on the final day of the season since 2011-12 when in the Championship.
This fixture is perhaps not as daunting on the face of it as it may seem, however, even if Watford have only won two of their last nine games since an incredible 3-0 win over Liverpool on February 29.
That is largely down to the fact that Arsenal have little to play for on the final weekend, with eighth place now the best they can hope for after the 1-0 loss to Villa in midweek.
Not since 1983 have they lost back-to-back matches against teams in the relegation zone, though, and Mikel Arteta will no doubt want to finish a disappointing Premier League campaign on a relative high.
The following weekend's FA Cup final against Chelsea provides Arsenal with an opportunity to salvage something from a disappointing 2019-20 campaign, and they will not want to go into that game on the back of successive league losses.
While Watford have struggled on the final day of the season down the years, the Gunners are unbeaten in their last 14 such matches, winning the last eight in a row.
Indeed, not since 1992-93, when going down 3-1 to bitter rivals Tottenham Hotspur, have they lost their final game of the season on home soil.
Arsenal's Premier League form: WWDLWL
Arsenal's form (all competitions) WDLWWL
Watford's Premier League form: LLWWLL
Given there is a six-day break between this game and the FA Cup final, it makes sense for Arteta to named his strongest possible lineup on Sunday, likely meaning a return to a 3-4-3 system.
Striker Pierre-Emerick Aubameyang has scored four goals in his four Premier League games against Watford, though three of those strikes have come at Vicarage Road.
Mullins has no fresh injury or suspension concerns on the back of the loss to Man City, but he may well elect to make changes in certain areas.
Arsenal possible starting lineup:
Martinez; Holding, Luiz, Tierney; Bellerin, Ceballos, Xhaka, Saka; Pepe, Lacazette, Aubameyang
Watford possible starting lineup:
Foster; Mariappa, Kabasele, Dawson, Masina; Doucoure, Chalobah, Hughes; Sarr, Deeney, Welbeck
We say: Arsenal 2-1 Watford
Regardless of the outcome on Sunday, this will be Arsenal's worst top-flight campaign since 1995. Watford will have to target all three points at the Emirates Stadium, knowing that Villa have the easier of the concluding fixtures, but the Gunners have a pretty formidable record on the final day and we can see them extending that winning run here.