Watford produced a fine defensive display to end Coca-Cola Championship leaders Reading's run of 10 straight home wins in the league.
Under pressure for much of the match, Adrian Boothroyd's play-off hopefuls resisted to claim a draw that will do their own promotion chances no harm.
The visitors enjoyed some lucky escapes - Brynjar Gunnarsson hit a post for Reading, and Malky Mackay and Lloyd Doyley both made goal-line clearances - while Reading remain within touching distance of the Barclays Premiership and will not be too despondent.
Reading made their intentions clear from the start, and Watford's defence quickly had their work cut out to keep their opponents at bay.
Jay DeMerit - who was excellent at the back - did well to block the recalled Dave Kitson's 15-yard effort after John Oster had robbed Matthew Spring in midfield in the 13th minute, and a minute later Steve Coppell's men screamed for a penalty when Mackay tangled with Kevin Doyle following Oster's ball over the top.
But the pace of Chris Eagles and Ashley Young meant Watford could always threaten on the counter-attack.
In the 21st minute, Eagles chipped in a cross that home goalkeeper Marcus Hahnemann could only palm into the path of Spring but, luckily for Reading, the midfielder shot wildly over.
Reading wasted another chance to go in front four minutes later when Kitson raced onto Doyle's flick but fired over from close range after being forced wide by Mackay.
Mackay was the hero for Watford eight minutes from the interval, hooking off the line after Ibrahima Sonko appeared certain to bundle in Kitson's flick after Bobby Convey's left-wing cross.
The visitors then swept downfield and Nicky Shorey did superbly to block Young's fiercely-struck effort from 18 yards to concede a corner.
Watford had another escape just before the whistle, Doyley hacking away Doyle's shot with goalkeeper Ben Foster stranded after ex-Hornet Gunnarsson had fired against a post.
Reading continued to enjoy more possession after the break, but they were far less incisive - and Watford were creating just as little.
As a result, the match went off the boil. Marlon King - surprisingly left out of Watford's starting XI - miskicked six yards out after replacing Anthony McNamee at half-time, and Eagles drilled a low shot straight at Hahnemann from 22 yards after good work by Spring.
With the passage of time Reading's verve returned, but they could not make the breakthrough as Watford hung on for an important point.
Teams
Reading Hahnemann, Murty, Shorey, Sonko, Ingimarsson,Oster (Hunt 76), Harper, Gunnarsson, Convey, Kitson, Doyle.
Subs Not Used: Stack, Halls, Makin, Long.
Booked: Convey, Gunnarsson.
Watford Foster, Doyley, Stewart, Mackay, DeMerit, Eagles,Mahon, Spring, McNamee (King 45), Young (Bangura 83), Henderson.
Subs Not Used: Chamberlain, Chambers, Carlisle.
Att: 23,724
Ref: S Tanner (Somerset).