However, all the pre-season optimism and belief quickly dissipated as the Hornets endured a torrid campaign that resulted in their relegation back to the Championship after finishing in 19th position.
Here, Sports Mole takes an in-depth look back at Watford's forgettable 2021-22 campaign.
SEASON OVERVIEW
Final league position: 19th
EFL Cup: Third round
FA Cup: Third round
Top scorer: Emmanuel Dennis (10)
Most assists: Emmanuel Dennis (6)
Watford began the Premier League season full of optimism after racking up 91 points in their promotion campaign to finish second in the Championship.
Having taken over the reins at Vicarage Road in December 2020, Xisco had enjoyed a successful period with the Hornets, and after guiding his side to promotion, the 41-year-old's main objective was to keep Watford in the top flight.
The season began with a 3-2 home victory over Aston Villa, getting the Hornets off to a dream start, but the positive atmosphere around the club quickly disappeared as the next six league matches yielded just four points.
Although the campaign had only entered October, Xisco was relieved of his duties, leaving Watford in 15th place with four points separating them from the drop zone.
Out went the young coach, while through the door came a wise head in the form of Premier League-winning manager Claudio Ranieri, who began his fourth spell as head coach in England after previously managing Chelsea, Leicester City and Fulham.
If the 70-year-old was not fully aware of the uphill task that lay in front of him then he was given a rude awakening when his new side fell to a heavy 5-0 defeat to Liverpool in his first game in charge.
Despite losing on his debut as Watford boss, Ranieri tried to work his magic and for a moment it seemed to work as Watford thrashed Everton 5-2 before they responded to consecutive defeats by clinching a surprise 4-1 victory over Manchester United that spelled the end for Ole Gunnar Solskjaer as United manager.
Following the emphatic win over the Red Devils, the stage was set for the Hornets to press forward, but the opposite proved to be the case, and following a run of one point in eight league games, Ranieri was packing up his belongings after becoming the second Watford boss to be sacked this term.
Ranieri's successor turned a few heads as Roy Hodgson made his return to the dugout, but rather than a fairytale ending to an illustrious managerial career, the 74-year-old oversaw a run of eight points from Watford's remaining 18 league games, which ultimately condemned the Hornets to the second tier after one season in the top flight.
PREMIER LEAGUE STATS
Wins: 6 (19th)
Draws: 5 (19th)
Losses: 27 (1st)
Goals scored: 34 (19th)
Goals conceded: 77 (3rd)
Yellow cards: 57 (15th)
Red cards: 3 (6th)
Passes: 13,046 (17th)
Shots: 399 (19th)
Big chances missed: 39 (10th)
Saves: 117 (10th)
Tackles: 614 (11th)
Own goals: 3 (3rd)
Hit woodwork: 11 (12th)
Clearances: 866 (1st)
HOW DID IT COMPARE TO LAST SEASON?
Watford's promotion-winning season was an unmitigated success as they cruised to a 91-point tally, averaging nearly two points per game compared to 0.61 points per game this term, while their previous Premier League campaign yielded 11 more points despite also finishing in 19th place.
The Hornets also found the net on two fewer occasions than the 2019-20 campaign, while their defence shipped 13 more goals, highlighting the deficiencies that have led to their demise this term.
They ended last season's Championship campaign with the best defensive record after conceding 30 goals in their 46 league matches, but in 38 Premier League contests this time around, they conceded 77 goals.
Watford fans witnessed their side average 1.84 points from their home matches on their way to second place in the Championship, but their experience was far less enjoyable in the top flight as the Hornets mustered a measly 0.42 points per game.
In regards to the cup competitions, Watford saw no improvement as they fell out of the FA Cup in the third round for the second season in a row, while their League Cup journey also ended at the same stage as last term, with the Hornets exiting the competition in the third round.
PLAYER OF THE SEASON - EMMANUEL DENNIS
Despite arriving in the January transfer window from Nice, Hassane Kamara was a contender for the player of the season after making a fine impression in his 19 appearances for the club.
The left-back has topped the Watford averages for tackles and interceptions made per game in the Premier League, highlighting the positive impact the 28-year-old has made at Vicarage Road since his arrival.
However, Kamara was pipped to the award by Dennis, who finished the campaign as Watford's top scorer after netting 10 of his club's 34 league goals this term.
Dennis also demonstrated that there are more facets to his game than just goals, with the Nigerian also picking up more assists than any of his teammates, while he was also involved in more shot-creating actions in the Premier League than any other Watford player.
The 24-year-old, who joined Watford from Club Brugge last summer, also topped the charts for successful dribbles in comparison to his colleagues, and though his team endured a poor campaign, Dennis can be satisfied with a promising season on an individual level.
STANDOUT RESULT
Unfortunately for Watford, a Premier League season that yielded only six victories does not offer much choice for a standout result.
The impressive 5-2 away win over Everton certainly catches the eye, but it would be impossible to ignore the superb performance from the Hornets on November 20 that resulted in Solskjaer's sacking as Man United boss.
Watford's home contest against United got off to a promising start when the hosts were awarded a penalty in the 11th minute, with Ismaila Sarr stepping up only to see his spot kick comfortably saved by David de Gea.
Kiko Femenia netted from the subsequent rebound, but the strike was ruled out for encroachment, presenting Sarr another opportunity to score from the spot.
The 24-year-old spurned his second penalty in a matter of moments as De Gea managed to get his right hand to Sarr's effort.
Rather than reeling from the penalty misses, the hosts kept the pressure on United, and their attacking intent was rewarded in the 28th minute when Joshua King guided the ball home, before Sarr drilled a powerful strike into the bottom corner on the stroke of half time to double their advantage.
Although Donny van de Beek halved the deficit after the break, a second yellow card for Harry Maguire halted any United comeback and a memorable win was sealed when Joao Pedro and Dennis both found the net in stoppage time.
BEST MOMENT
After finishing 15 points adrift of safety, potential best moments for Watford were few and far between, although any of the four goals in the thrashing of Man United were contenders for the award.
However, the best moment of Watford's season goes to Cucho Hernandez's audacious acrobatic strike against Arsenal at Vicarage Road in February.
The Hornets fell behind early in the contest following Martin Odegaard's fifth-minute opener, but six minutes later the hosts were back on level terms thanks to a spectacular equaliser from Hernandez.
With his back to goal as Kiko's lofted cross drifted towards him, there seemed little on in terms of shooting opportunities for Hernandez, but seemingly out of nowhere the striker propelled himself into the air before sweetly connecting with a superb overhead kick from 12 yards out to pull his side level.
Unfortunately for Hernandez, his effort was in vain as Watford were edged out via a 3-2 scoreline, but those in attendance left Vicarage Road with one particular effort at the forefront of their minds.
TOP PRIORITY FOR SUMMER
With Hodgson departing following the conclusion of his short-term deal, Watford have wasted no time in appointing his successor.
Rob Edwards has been plucked from Forest Green Rovers after guiding the side from Nailsworth to the League Two title, ensuring that Rovers will participate in the third tier of English football for the first time in their history.
The new boss will certainly be busy over the summer with key players set to depart; the likes of Dennis, Sarr, King, Pedro, Moussa Sissoko and Juraj Kucka are all expected to leave in what promises to be a busy transfer window.
With a number of forward-thinking players set to go through the exit door, Edwards will be looking for reinforcements in the final third, as they bid to return to the top flight at the first time of asking.
At the other end of the pitch, Edwards will assess whether he needs to go into the market for a goalkeeper following Ben Foster's departure, but with Maduka Okoye set to come into the club from Sparta Rotterdam, Watford may be content with Okoye and Daniel Bachmann battling it out for the number one jersey.
FINAL VERDICT
After falling well short of safety, Watford will not look back on the 2021-22 season with too many fond memories, while their performance in the cup competitions offered no relief.
With six of their 38 league matches resulting in victory, there was not too much for the Watford faithful to enjoy, although the 4-1 win over Manchester United was a momentary bright spark.
In truth, the Hornets will want to quickly forget the campaign as they begin to prepare for a promotion bid under the guidance of their new manager.