Newport Gwent Dragons' season came to a humiliating end when they were thrashed by Welsh rivals Llanelli Scarlets in their Celtic Cup quarter-final last night.

The Dragons showed no fire at all and their abject performance just about summed up the second half of their season. They did rally with three tries in the final quarter, but they were 42-0 down by then.

They were embarrassingly outpaced by a rampaging Scarlets team and conceded five tries, three of them in a five-minute second half spell.

It was the heaviest defeat the Dragons have suffered in the two years they've been going and their first home defeat by a fellow Welsh team.

It was also Percy Montgomery and Rod Snow's final appearances for the Dragons, Monty's ending ingloriously midway through the second half when he was replaced.

The Scarlets were quickly into their stride, young outside half Ceiron Thomas kicking a third minute penalty - when Gareth Baber went over the top - after missing an earlier shot.

Sweeney had a chance to level the scores, but was wide with a long range effort, a miss made worse when Thomas doubled the lead with his second penalty after Gough was harshly penalised following a skirmish with opposite number Chris Wyatt.

The Dragons opened out, putting the ball through several phases with Michael Owen prominent, only for Sweeney to miss another penalty shot.

The Scarlets twice went desperately close when Tal Selley was held over the line and when Luke Charteris got across to halt Aisea Havili inches short, but there was no escape and Selley romped over for a try unopposed. Thomas converted for a 13-0 lead after 20 minutes. The Dragons hit back with Charteris streaming through after being fed by Rhys Thomas.

But the Scarlets struck again when Wyatt won a line-out, Thomas brushed aside an attempted tackle by Sweeney and Havili strolled over for an easy try near the corner which Thomas improved.

At last the Dragons showed some fire when they drove the Scarlets 40 yards downfield, but Sweeney sliced his penalty kick to touch.

Almost on the interval Dragons captain Jason Forster and Scarlets prop Phil John were yellow carded after punches were thrown. The penalty went the Scarlets' way and full back Barry Davies stepped up to strike the ball through the uprights from near halfway for the hapless Dragons to trail 23-0 at the interval.

Watching Wales assistant coach Scott Johnson and team manager Alan Phillips must have been as dismayed as the fans at the home performance.

Craig Warlow replaced Jon Bryant for the second half, though in his normal outside half position with Sweeney moving to inside centre.

Though the Dragons showed greater urgency they went even further behind when a wild pass in the Scarlets 22 presented the ball to Havili and he raced clear on an 80 yard run for the line and his second try.

There was no respite for the Dragons and they conceded a fourth try when Dwayne Peel booted the ball downfield from his own 22 and Garan Evans comfortably won the race for the touchdown. Thomas converted.

Former Newport number eight Andy Powell was yellow carded for a high tackle on Rhys Thomas, but it made no difference to the rampaging Scarlets and another high speed attack ended with Selley romping across for the Scarlets' third try in five minutes. Thomas again converted.

Percy Montgomery's Rodney Parade career came to a premature end when he was replaced after 57 minutes, an ignominious way for him to finish.

The Dragons finally crossed the tryline after 64 minutes when Sione Tuipulotu powered over for Sweeney to convert.

That heralded a mini revival with the Dragons scoring two more tries in the last ten minutes, Sweeney from a neat pass by Craig Warlow and Ben Breeze when he chased a kick through, but it was all too late and the Scarlets had the last word when Selley completed his hat-trick and Thomas converted.

Newport Gwent Dragons: K Morgan, G Wyatt, P Montgomery (S Tiupulotu 57), J Bryant (C Warlow 40), B Breeze, C Sweeney, G Baber (G Cooper 57), A Black (R Snow 61), S Jones (J Richards 70), R Thomas (C Anthony 61), I Gough, L Charteris (P Sidoli 76), R Oakley, M Owen, J Forster (captain). Scorers - tries: S Tiupulotu, C Sweeney, B Breeze; conversions: C Sweeney (2). Llanelli Scarlets: B Davies, G Evans, M Watkins, T Selley, A Havili (J Mills 73), C Thomas, D Peel (M Phillips 73), P John, M Rees, J Davies (D Maddocks 65), A Jones (V Cooper 65), C Wyatt, S Easterby (captain), A Powell (G Quinnell 65), G Thomas (D Maddocks 41-49). Scorers -- tries: Selley (3), Havili (2), G Evans; conversions: Thomas (3); penalties: Thomas (4), Davies. Referee: Mr A Lewis (Ireland). Attendance: 3,364.