Hornets captain Troy Deeney had the best opportunity to win it from the spot after Jan Vertonghen handballed Gerard Deulofeu's shot inside the box, but his effort was saved by Paulo Gazzaniga.
Up the other end Tottenham were inches from snatching victory but Erik Lamela's deflected shot was cleared off the line by Watford debutant Nacho Pussetto.
Spurs have now gone three hours and 15 minutes of Premier League football without a goal as they continue to feel Harry Kane's absence - they are also winless in their last six games without their captain and talismanic striker.
Man of the match
"He's been a bit of a throwback today" - Glenn Hoddle
"I've been impressed with him today.He's a little bit of a throwback, he likes to get wide and attack his full-back.
"For me, he's been one of the better players today.
"Sarr has been excellent, putting a decent shift in defensively and getting to the byline when his team have gone forward."
View from the dugout
"Goal-line technology does not make mistakes like VAR"
Tottenham manager Mourinho could not resist a dig at VAR as he rued the two-millimetre margin that prevented Erik Lamela's shot from crossing the line and handing Spurs a valuable away win.
View from the dressing room
"I won't apologise for missing the penalty"
Hornets captain Deeney refused to blame himself for Watford's failure to pick up a fifth win in six games, despite fluffing his lines from the spot.
Tweet of the game
Picture of the game
After months of darkness, the sun is finally rising on Watford's Premier League campaign.
o Tottenham have failed to score in three consecutive Premier League games for the first time since November 2013. It’s also just the second time a side managed by Jose Mourinho has failed to score in three league games in a row (Man Utd, October 2016).
o This result ended a run of 93 Premier League games without a 0-0 draw for Tottenham, the second longest such run in the competition’s history (Man Utd, 114 games ending May 2002).
o No side has kept more Premier League clean sheets than Watford so far in 2019-20 (8). However, the Hornets have also failed to score in a league-high 11 Premier League games this season.
o Tottenham kept their first Premier League clean sheet away from home in 382 days, since winning 3-0 at Cardiff on New Year’s Day 2019.
o There were 32 shots without a goal in this match, the most in a Premier League game without there being a goal since Crystal Palace v Cardiff in December 2018 (40).
o Watford’s Troy Deeney has failed to score three of his last six Premier League penalties – he’d only missed one of his first 13 taken in the competition.
o Tottenham are winless in their last six Premier League games in which Harry Kane has played no part (D3 L3), with the Lilywhites failing to score on four occasions in that run.
Aston Villa (A) - Tuesday 21 January, 19.30pm
Tranmere (A) - Saturday 23 January, 7.45pm (FA Cup third round replay)
Everton (H) - Saturday 1 February, 3pm
Norwich (H) - Wednesday 22 January, 7.30pm
Southampton (A) - Saturday 25 January, 3pm - (FA Cup fourth round)
Manchester City (A) - Sunday 2 February, 4.30pm
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