Fulham were held to an FA Cup third-round replay after failing to convert their superiority over Watford into victory at Vicarage Road.

The Championship underdogs competed gamely and created several fine chances but had Fulham showed a little more composure in front of goal there would be no need for the rematch at Craven Cottage.

They took the lead through Zat Knight early in the first half but a penalty, conceded by Liam Fontaine during a goalmouth scramble, was then tucked away by Heidar Helguson four minutes before half-time.

Fulham may enter the replay with some trepidation as history suggests they will taste defeat - the sides have met twice before in the FA Cup with Watford drawing both matches at Vicarage Road before winning the return away from home.

The Cottagers will be especially disappointed as they had the star of the show in Luis Boa Morte and Newcastle - Graeme Souness has expressed his interest in the player - are unlikely be the only club seeking his signature during the transfer window.

Boa Morte was restored to the side against Crystal Palace on New Year's Day following a month in the treatment room and the impact he has had can not be overstated, as he proved once again today.

He was Fulham's most dangerous player - although there were stirling contributions from Steed Malbranque and Collins John - and it is little surprise the Cottagers have declared he is not for sale.

The first real chance was created by John on the opposite flank, however, with the Dutch forward collecting a long pass from Andy Cole and slipping it past Jermaine Darlington.

The Watford defender was well beaten and John enjoyed a free run to the edge of the area where his powerful shot cannoned off the far post with veteran keeper Alex Chamberlain floundering some distance from the shot.

Fulham continued to press with Malbranque and Boa Morte looking lively but the next real opportunity fell to Watford who saw a blistering drive from Paul Devlin denied by van der Sar's quicksilver reactions.

Inevitably, however, the Cottagers claimed the opener in the 17th minute when Mark Pembridge floated a pinpoint free-kick to the far post where towering centre back Knight outjumped Watford's defence and nodded home.

John almost made it two an heartbeat later but Chamberlain was alert to the threat and Malbranque went on a marauding run down the right only for his cross to sail out of danger with Fulham players queuing up in the box.

Watford should have equalised in the 26th minute when Hameur Bouazza slipped past Liam Rosenior and fed to Devlin but the striker failed to control his header when the ball should have found either corner.

USA international Carlos Bocanegra cleared the danger but the move prompted a purple patch from the home side who began attacking Fulham's defence with greater self-belief.

Bouazza and Darlington combined to good effect down the right with the midfielder racing to the byline but no-one was there to meet his final pass which slipped across the face of goal.

Boa Morte and Malbranque showed similar understanding on the edge of the area and the Portuguese international's shot was cleared away as far as John who blazed high over the bar from close range.

Watford were given the chance to equalise from the spot in the 42nd minute when Fontaine brought down Hameur Bouazza and Heidar Helguson made no mistake.

Cole shook off his marker with a neat turn five minutes after the restart but then smashed a fearsome effort wide of the right post as Fulham emerged for the second half with renewed determination.

Malbranque set-up Cole after a perfectly-timed tackle from Pembridge had initiated a fresh Fulham assault but Chamberlain reacted swiftly when the former England striker's first touch had proved too strong.

Helguson nodded over the bar from six yards out after being teed up expertly by Chambers and justifiably hung his head in shame after squandering such a magnificent chance.

Van der Sar kept out a stinging drive from Gavin Mahon following an aerial scramble that prompted a few worrying moments for visiting fans but in the 81st minute it was Watford's turn to be fearful as Malbranque hit the bar.

Neither side could create another decent chance and Fulham boss Chris Coleman will have been left shaking his head at the prospect of having another match added to the fixture list.

Teams

Watford Chamberlain, Chambers, Cox, Demerit, Darlington, Devlin (Dyer 82), Gunnarsson, Mahon, Ardley (Webber 66), Bouazza (McNamee 76), Helguson.

Subs Not Used: Doyley, Blizzard.

Goals: Helguson 42 pen.

Fulham Van der Sar, Rosenior, Knight, Fontaine, Bocanegra, Malbranque, Pembridge, Legwinski (Clark 83), Boa Morte, John, Cole.

Subs Not Used: Volz, McBride, Crossley, Rehman.

Booked: Bocanegra.

Goals: Knight 17.

Att: 14,896

Ref: A D'Urso (Essex).