The Premier League champions maintain Terry could yet still be offered a contract extension, despite his claim after last Sunday's FA Cup win at MK Dons that there will be no 19th season and no fairytale ending.
The likelihood Chelsea will be playing European football next term receded further at Vicarage Road, despite Guus Hiddink extending his unbeaten run in caretaker charge to nine matches.
Five of Hiddink's seven Premier League games have been draws, including against Watford on Boxing Day, leaving the Blues 15 points adrift of fourth-placed Arsenal.
Once again the Hornets tested Chelsea, but the visitors were denied victory when Diego Costa's 88th-minute header was kept out by Heurelho Gomes.
The visiting supporters made their feelings clear by repeatedly singing about captain Terry, on his 697th appearance, but their thoughts have fallen on deaf ears before.
Vocal supporter backing did little for Jose Mourinho, whose second spell came to an end in December.
But Terry can expect the fans to make their feelings clear to the club's hierarchy and owner Roman Abramovich in Sunday's clash with Manchester United at Stamford Bridge.
Hiddink says Terry is playing "perfectly", yet Watford's strikeforce proved a difficult proposition, with Odion Ighalo's movement particularly tricky for the Blues skipper to track.
Watford were on top for much of the first half and it was a sign of frustration at things not going the visitors' way when Costa and Juan Carlos Paredes were involved in a petty exchange which saw both players booked for their amateur dramatics.
Costa made his presence felt early on by pushing Craig Cathcart to the floor and was spoken to by referee Mike Dean.
Cathcart next tracked Costa and blocked a shot and the striker later saw an effort deflect narrowly wide off the defender
In between efforts, Watford were well on top.
Terry conceded a free-kick for climbing over Deeney
"Sign him up," chanted the Chelsea fans as Watford wasted the set-piece.
The Hornets looked for openings and the best came when Jose Holebas crossed from the left, but Ighalo could not get a clean connection.
Sebastian Prodl met Ben Watson's corner with a firm header, but it was straight at Thibaut Courtois, who next denied Etienne Capoue from a promising position.
There was so much incident in the 26th minute that the anticipated ovation for Terry, who wears shirt number 26, did not materialise.
Costa was regularly running down the left channel and he went down softly under Paredes' challenge before reacting angrily.
The Watford right-back appeared to anticipate retribution when the pair were next in close proximity, going to ground under minimal contact
Both players were booked.
Hiddink told Costa to focus on the football and the striker almost created a goal for Oscar, only for his cut back to be prodded wide.
Troy Deeney shot narrowly wide across goal before Eden Hazard tried to spark Chelsea to life.
Hazard teed up Branislav Ivanovic, but Gomes was equal to the shot.
Willian next fed Hazard, but he took a heavy touch and Gomes smothered the ball before denying Costa from Willian's cross.
TWEET OF THE MATCH
"If I was offered looking like Quique Sanchez Flores when I turn 50, I'd take it right now
Bite your hand off, in fact" - With less than stellar entertainment on the pitch, Guardian sports writer @SachinNakrani allows his attention to wander.
PLAYER RATINGS
Watford
Heurelho Gomes: 8 (out of 10)
Juan Carlos Paredes: 6
Jose Hoelbas: 7
Sebastian Prodl: 7
Craig Cathcart: 7
Ben Watson: 7
Etienne Capoue: 6
Valon Behrami: 6
Troy Deeney: 7
Odion Ighalo: 8
Jose Manuel Jurado: 7
Substitutes:
Almen Abdi (for Jurado, 64 minutes): 6
Allan Nyom (Paredes, 68): 6
Mario Suarez (for Capoue, 86): 5
Chelsea
Thibaut Courtois: 6
Branislav Ivanovic: 6
Cesar Azpilicueta: 6
Kurt Zouma: 7
John Terry: 6
Nemanja Matic: 5
John Obi Mikel: 6
Oscar: 6
Diego Costa: 6
Cesc Fabregas: 7
Willian: 6
Substitutes:
Eden Hazard (for Matic, 72): 6
STAR PLAYER
Heurelho Gomes
Made a number of key interventions to deny Ivanovic, Hazard and Costa.
MOMENT OF THE MATCH
It looked like Chelsea were going to claim a late victory when Willian crossed from the right in the 88th minute and Costa met the ball, but Gomes made a fine save.
VIEW FROM THE BENCH
Chelsea reverted to the side which won at Arsenal, with Hazard kept in reserve ahead of Sunday's match with Manchester United
Yet they lacked attacking intent as Watford kept them occupied in defence
The Hornets made two enforced chances, with Prodl and Holebas in for Miguel Britos (illness) and Nathan Ake, who was not permitted to face his parent club
Hazard tried to turn the game in Chelsea's favour from the substitutes' bench, but found Gomes on form.
MOAN OF THE MATCH
More theatrics from Costa, this time involving Paredes, who was equally culpable for their pathetic squabble late in the first half
Costa's involvement was a sign of frustration that things were not going Chelsea's way.
WHO'S UP NEXT
Tottenham v Watford (Barclays Premier League, Saturday, February 6)
Chelsea v Manchester United (Barclays Premier League, Sunday, February 7)
Source : PA
Source: PA