Sunderland boss Sam Allardyce wasn't shying away from the importance of the Watford game pre-match.
But the Black Cats boss was left to reflect on what could have been after a woeful first-half performance cost his side dear.
Trailing from the fourth minute, Sunderland couldn't find any quality, rhythm or momentum until deep into the second half.
So, what did we learn from the defeat?
Allardyce shows his ruthless streak...after just 19 minutes:
Sunderland were getting torn apart.
The Hornets posed a huge threat, with Watford doubling up down the flanks, whipping in some dangerous crosses.
Odion Ighalo netted his 10th goal of the season after just four minutes, although replays showed Sebastian Coates may have got the last touch.
Something had to give. And it did. Allardyce acted.
DeAndre Yedlin hooked after just 19 minutes, Jack Rodwell on in his place as Sunderland switched to a flat-back four.
It was better from then on defensively, mind, it certainly couldn't have been any worse.
Watford did a job on Sunderland first half:
It is never a good sign for a manager if they have to change their tactics just 19 minutes into a game.
But the Hornets had done their homework and did a job on the Black Cats in the opening half hour.
Wave after wave of attack combined with some very ropey defending could have seen Watford 3-0 up at half-time.
Whether it was down to personnel or the 5-4-1 system, Watford dominated the opening 20 minutes, which ultimately won them the match.
Waford exposed them down the flanks and made the most of Younes Kaboul's absence. His absence was a massive loss.
Sunderland can't play a back three if John O'Shea, Younes Kaboul and Sebastian Coates aren't all fit:
The Everton away game and the first 20 minutes at the Stadium of Light against Watford proved this.
If those three are fit, Sunderland look solid at the back, well organised and compact.
If anyone of them are missing, it all goes to pieces.
It was no surprise to see them quickly switch to a flat-back four.
Winter of discontent looms...
Watford at home had been described as a major game for Sunderland by boss Sam Allardyce, a 'six-pointer'.
It was a chance to climb out of the bottom three and to secure a third win in four ahead of some very tricky festive fixtures.
But a fourth minute hammer-blow cost them dearly.
And now they face trips to Chelsea and Manchester City and a home game against Liverpool before 2015 is out.
The Black Cats needed something from this game to keep their momentum going.
Instead it is back-to-back defeats heading into a particularly tough period.
Mind, even Bournemouth beat Chelsea at home...
Surely, Jermain Defoe has to start:
We didn't learn this after the Watford defeat, we learned this months ago.
But the 1-0 loss again highlighted the importance of Defoe to this struggling Sunderland side.
He came off the bench after 72 minutes but was Sunderland's brightest player, carving out three good openings, earning this reporter's man of the match gong.
Watford are flying high and a huge part of their success has been the form of Odion Ighalo and Troy Deeney.
In this most demanding of leagues you need your goalscorers out on the pitch.
Expect to see Defoe start at Stamford Bridge.
And finally, some good news as John O'Shea makes it 400*:
The Sunderland captain became the 34th player in the history of the Barclays Premier League to reach 400 games in the top flight.
An excellent achievement by the former Manchester United defender.
Mind, O'Shea -who will be heading to France next summer with the Republic of Ireland for Euro 2016 - won't want to remember this landmark game for too long though.
Sunderland were poor and defensively all over the place in the opening 20 minutes.
The Irishman is the third Republic of Ireland player to reach 400 Premier League appearances after Shay Given (443) and Richard Dunne (431).