WATFORD'S Carling Cup adventure finally ran out of fizz at Vicarage Road tonight after Steven Gerrard - as he had done at Anfield a fortnight ago - again proved the difference between the two sides and it was his second-half goal which sent Liverpool to Cardiff next month for the final of the competition following their 1-0 victory (2-0 on aggregate).

What was in truth a drab affair, lit up by an electric Vicarage Road atmosphere, neither side created a meaningful effort on target - the goal apart - and although Watford did have a strong penalty claim late in the first-half when Steve Finnan looked to have hauled down Hameur Bouazza, this was a case of what might have been' for the Hornets, who just never quite got going in the final third of the pitch.

To be fair to Ray Lewington's side though, Liverpool came here content to settle for a draw, and played with lone striker Fernando Morientes ahead of a five-man midfield which stifled the home side and turned this into a war of attrition. Liverpool, in every sense of the word, ground out victory.

For the biggest match at Vicarage Road since the Division One play-off semi-final against Birmingham City in 1999 Lewington reverted to the side which did do well at Anfield in the first leg and switched back to a 4-5-1 formation after employing a 4-4-2 at Wigan Athletic on Saturday.

Following their 2-0 defeat at Southampton Benitez made three changes and, intriguingly, opted to match Watford's 4-5-1 shape. Djimi Traore replaced the injured Sami Hyypia and Finnan recovered from his hamstring injury to come in for Stephen Warnock, who was on the bench, at left-back. The other change saw Igor Biscan replace Luis Garcia, but Milan Baros moved out to the right leaving £6.3m man Morientes as the loan striker.

Despite the fervent home support, it was the visitors who were first to settle and, worryingly for Watford, Gerrard, playing just behind Morientes, looked in the mood and twice found John Arne Riise in space on the left but the Norwegian international was unable to provide a telling cross.

Gradually, Watford began to ease themselves into the game though and Bouazza made a darting run through the Reds midfield and released Heidar Helguson, but the Hornets' leading scorer had just strayed off-side.

Then, a Darlington break down the left, after Bouazza had done well to rob Baros, also ended in nothing after the former MK Dons man overplayed his final ball through for Neal Ardley to chase.

Watford forced their first corner of the match on 22 minutes after Devlin's cross had been blocked but Ardley and Mahon over-elaborated the set-piece and the chance was wasted without the visitors' defence being tested.

At the other end, Gerrard and Morientes also tried to be clever with a corner from the right and although Riise had to time to shoot he skewed well wide.

The Hornets did have a scare on 26 minutes though when Morientes and Gerrard linked well but the ex-Real Madrid man saw his low shot deflected off and just Cox just wide of Paul Jones' left-hand post.

But Watford did have their first effort at goal a minute later when Helguson chested Cox's free-kick into the path of Mahon but he pulled his shot well wide of Jerzy Dudek's right-hand post from 22 yards.

Gerrard uncharacteristically lost his composure when he spear-headed a Liverpool three-on-one break and failed to pick out Baros, who was in acres of space and, as the cup-tie finally came to life, Bouazza then wasted a good chance to cross into the danger zone after another break from Darlington down the Watford left.

Riise looked to have opened up a decent shooting chance for himself five minutes before the break after cutting inside Chambers but ballooned over before Watford produced their best moment of the half; DeMerit lofted a lovely ball down the right for Ardley to chase and he drilled a dangerous ball low across goal but Finnan cleared the danger with Bouazza lurking.

Bouazza then latched onto a clever Ardley throughball but, just about to pull the trigger, Finnan robbed the French youngster with a tackle, although just how much he got of the ball was debatable.

Half-time: 0-0 Morientes should have done better from a Riise cross almost immediately after the restart but skewed his header well wide after rising above DeMerit.

Then Cox produced a vital tackle to deny Baros after the Czech international had, for once, broken clear of Darlington.

Despite the early flutter from Liverpool, it was Watford who erupted into action on 55 minutes. Helguson sprayed the ball wide to Bouazza who played it back for Darlington. Darlington cut inside Finnan and shot low across Dudek but Mauricio Pellegrino hacked the ball away.

Liverpool then had a decent penalty appeal of their own when Chambers appeared to trip Gerrard but again Mike Riley waved play on.

The disappointing Morientes almost created a yard of space on 68 minutes, but DeMerit quickly recovered to block the shot from just inside the area.

Biscan's deflected shot then presented Liverpool with a corner in the 73rd minute, and, from Riise's whipped in set-piece, Morientes flicked the ball towards goal but Brynjar Gunnarsson cleared.

And, in keeping with the game, it was a scrappy goal that put Liverpool ahead on 76 minutes. Watford lost possession midway in their own half and Gerrard picked up, drove forward and, from just inside the Hornets penalty box shot low across Jones and into the keeper's bottom right-hand corner.

McNamee added some much-needed to spark to the Watford attack in the latter stages, but, by this time, the battle-weary Hornets seemed resigned to their fate.

Watford: Jones; Chambers, Cox, DeMerit, Darlington; Devlin, Gunnarsson, Mahon, Ardley, Bouazza; Helguson. Substitutes: Webber for Bouazza after 55 mins; Dyer for Gunnarsson after 77 mins; McNamee for Devlin after 80 mins. Chamberlain, Doyley not used.

Liverpool: Dudek; Finnan, Carragher, Pellegrino, Traore; Baros, Hamann, Gerrard, Biscan, Riise; Morientes. Substitutes: Sinama-Pongolle for Baros after 85 mins; Garcia for Sinama-Pongolle after 87 mins; Potter for Gerrard after 90 mins. Warnock, Carson not used.

Bookings: None.

Attendance: 19,797 (4,620 Liverpool).

Referee: Mike Reilly (Leeds, West Yorkshire).