The Hornets and Spurs have won three matches from three this month to join Liverpool and Chelsea on nine points at the top of the division, but something has to give this weekend.
Never in their top-flight history have Watford won three from three to start a season, and they are now aiming to win four in a row at any level for just the second time, having previously achieved that feat in the second tier 30 years ago.
Javi Gracia's men have profited from a rare summer of stability that saw limited transfer activity at Vicarage Road - they even managed to make a profit - and a manager remaining on through pre-season for the first time since their return to the top flight.
Backed as favourite to become the first manager sacked with many bookmakers, Gracia has found a settled XI - naming the same side three league games running - and the reward for Watford is their best ever start to a Premier League campaign that promises so much.
The 2-0 win over Brighton & Hove Albion on the opening day was as straightforward as Prem victories come; Roberto Pereyra netted twice to continue his impressive form that has seen him play a direct part in nine goals in his last nine outings on home soil.
Watford then saw off a fatigued Burnley 3-1 at Turf Moor, racking up their first away goals under Gracia in the process, before battling to a 2-1 victory over Crystal Palace last weekend to keep their perfect run intact.
Only once before have the Hornets enjoyed a longer winning streak in the Premier League, going four matches without dropping points in December 2014, and Gracia now looks good value to become the first Watford boss since Gianfranco Zola to remain in the job for longer than 12 months.
Winning breeds confidence, they say, and if the Hertfordshire outfit can make it four from four on Sunday afternoon then their pre-season objectives may have to be altered slightly.
Recent form in Premier League: WWW
Recent form in all competitions: WWWW
While Watford managed to turn a profit during the summer transfer window, they did at least bring in Gerard Deulofeu on a permanent basis and add the likes of Domingos Quina, Ben Foster and Marc Navarro to their squad.
Tottenham, on the other hand, became the first team since the summer transfer window was introduced in 2003 to not make a single signing, reportedly missing out on top targets Wilfried Zaha and Jack Grealish. Stability, then, is something that the Lilywhites have in abundance.
Not that a lack of new recruits has proved much of a problem for boss Mauricio Pochettino, who has kicked off his fifth season at the North London helm with three impressive wins, most recently overcoming Manchester United 3-0 at Old Trafford.
Tottenham had failed to so much as score at the Theatre of Dreams on their four previous visits under Pochettino, but an improved second-half showing saw them come out on top clear winners, courtesy of a Lucas Moura brace and a goal for Harry Kane - his August drought is now well and truly over.
That fourth win at Old Trafford in 40 years, and the Lilywhites' biggest triumph there since 1972, was described as "massive" by Pochettino and Kane, as they proved that they can once again hold their own in the higher reaches of the division, even if many had written them off due to stagnation.
Pochettino's men now have more points in 2018 than any other side in the Premier League - more even than last term's runaway champions Man City - winning 15 and drawing four of their 21 outings since the turn of the year.
Spurs have also now won their first three away league games in back-to-back seasons, having failed to do so in more than a quarter of a century. Only Man City took more points on their travels last term than Tottenham, with the Londoners winning more than half of their 19 away outings and drawing four.
The famous 3-0 win over United will clearly stick in the mind for a while yet, but Pochettino knows that his side must now push on and ensure that they stick with the rest of the challengers in what could be a thrilling title race.
Recent form in Premier League: WWW
Gracia made 11 changes to his starting lineup for the 2-0 win over Reading in the EFL Cup second round in midweek, but he is expected to revert back to the XI that started against Brighton, Burnley and Palace.
Deulofeu is in contention to feature, though will likely have to settle for minutes from the bench at best, while Miguel Britos is considered a doubt.
Erik Lamela may be considered for selection after sitting out the win at United, but the big call for Pochettino to make is whether to go with four at the back or five.
Watford starting lineup:
Foster; Holebas, Kabasele, Cathcart, Janmaat; Pereyra, Doucoure, Capoue, Hughes; Deeney, Gray
Tottenham Hotspur possible starting lineup:
Lloris; Trippier, Alderweireld, Vertonghen, Davies; Dier, Dembele; Lucas, Dele, Eriksen; Kane
Head To Head
Watford have a terrible record against Spurs, particularly in the Premier League as they have failed to win any of the previous 10 encounters.
Tottenham have won seven of those, including seven of the last eight, and drawn the other three since their first meeting in the competition just under two decades ago.
Taking all competitions into account, the Hornets have just seven wins in 45 games, last coming out on top in their 1994 EFL Cup second-round tie, although Spurs still went through 8-6 on aggregate.
We say: Watford 0-2 Tottenham Hotspur
Watford have started the season strongly and have the potential to finish in mid-table. Tottenham will be expected to remain in the top four of the division all season long, meanwhile, and they will see this fixture as another chance to put three more points on the board.