Heidar Helguson enhanced his growing reputation with a first-half double as
Watford gained revenge for their drubbing at Crewe earlier in the season.
American defender Jay DeMerit, who was playing in the Ryman League with
Northwood last season, stretched the lead with his first goal for the club at
the start of the second half.
Luke Varney gained some reward for his tireless display with a 68th-minute
consolation for Dario Gradi's side.
Iceland international Helguson, who gave the Liverpool defence plenty of
problems in the Carling Cup semi-final in midweek, opened the scoring after just
nine minutes.
Gavin Mahon split the defence with a long ball down the middle which Helguson
controlled on his chest before rifling a fierce volley into the roof of the
net.
Helguson had gone close to breaking the deadlock five minutes earlier when his
header from a Paul Devlin cross struck the crossbar.
Seconds later Neal Ardley's corner was only half-cleared into the path of
James Chambers, whose fierce shot took a vital deflection off Richard Walker.
The Hornets continued to lay siege to the visitors' goal as Kenny Lunt
deflected a Jermaine Darlington shot away for a corner in the fifth minute.
But Helguson finally struck the opener, while at the other end Varney missed a
couple of decent opportunities to equalise.
However, Watford were still looking dangerous and it came as no surprise when
Helguson fired home his 16th goal of the season in the 29th minute.
Chambers took advantage of a slip by left-back Walker to send a great cross
into the area for Helguson to control the ball near the penalty spot before
drilling the ball into the bottom corner.
The Railwaymen, without striker Dean Ashton after his £3million move to
Norwich, carved open another chance in the 37th minute which went begging.
Lunt sent in a cross for David Vaughan only for the midfielder to fire his
effort wide from close range.
Ray Lewington's men shot out of the blocks after the restart and surged
further ahead just 32 seconds into the second half.
Centre-back DeMerit, only in the side because of a groin injury to skipper
Sean Dyche, went on a run from the centre circle and unleashed a low shot into
the corner from the edge of the area.
Crewe keeper Clayton Ince was forced into action in the 54th minute when he
managed to push Chambers' shot round the post for a corner.
Varney continued to prove a thorn in the Hornets defence, curling a shot over
the crossbar moments before he finally pulled one back for Crewe against the run
of play.
The 22-year-old striker beat the offside trap following Vaughan's through-ball
and rolled the ball past keeper Paul Jones.
Lewington made a flurry of substitutions to take the sting out of the game,
bringing on Dominic Blizzard, Anthony McNamee and Johnnie Jackson.
And the tactic worked as the Railwaymen rarely threatened to reduce the
deficit further.