Newport Gwent Dragons slumped to a disappointing defeat in their final game of the season at Rodney Parade last night, an experienced Ulster team winning at the ground for the first time since 2006.

The Dragons failed to reproduce the form which vanquished the Ospreys and Cardiff Blues, making a hatful of mistakes which will have had their coaches fuming.

Defensive errors accounted for all three of Ulster’s first half tries, two of them by centre Nevin Spence, and far from settling for the one point they needed to secure a Magners League playoff place the visitors got four for the victory.

The Dragons were strangely lethargic, the midfield was suspect and Steffan Jones was exposed at full back far more than last week.

On top of that leading outside half Jason Tovey was a first half casualty with a knee injury and though he returned for a spell had to depart for good after 42 minutes.

But the Dragons did improve in the second half and Tom Riley’s try, converted by replacement Matthew Jones, meant they at least gained a losing bonus point.

And Edinburgh’s defeat in Treviso means the Dragons finished the campaign in a creditable seventh position with the prospect of better to come next season.

Ulster looked dangerous from the off, full back Adam D’Arcy running back a stray Aled Brew clearance and Craig Gilroy menacing, but though the Dragons cleared they gave away a penalty for preventing release and Ian Humphreys slotted the kick for an early 3-0 lead.

And defensive slackness allowed Ulster to snatch their first try soon after. Centre Spence bravely went for broke, a gap opened up invitingly for him and he strode on, outpacing the covering Steffan Jones for a fine solo try which Humphreys failed to convert.

The Dragons hit back swiftly and Brew seemed set for yet another try when Jason Tovey made a half break, handed on to Adam Hughes who put his fellow winger clear but referee Alan Lewis ruled Tovey’s pass was forward.

The outside half went down in the next attack and limped off, replaced by Matthew Jones after only 16 minutes.

But the Dragons still piled on the pressure and Toby Faletau went close, then Ruan Pienaar had a kick charged down and finally the Dragons were awarded a penalty which replacement Jones kicked to narrow the gap to five points.

But Ulster quickly regained the initiative, No 8 Robbie Diack storming through another gap, then the dangerous Spence was hauled down by a Matthew Jones cover tackle.

But Spence benefited from a defensive muddle near the touchline and when the ball squirted loose infield he pounced on it for his second try, awarded after a ruling by the TMO.

Tovey returned, his knee strapped up, and he proceeded to inspire a succession of attacks with some tricky running and soft hands.

And when the Ulster forwards infringed for the umpteenth time Tovey calmly slotted the penalty when their efforts deserved better.

But instead it was Ulster who got their third try as heavy rain fell.

Their line-out throw went astray over the top but when the ball bounced awkwardly blindside Pedrie Wannenburg pounced on it for the try which Humphreys converted for a 20-6 interval lead.

Tovey lasted only two minutes into the second half before limping off again, Jones back on and the replacement was unlucky to see a penalty attempt strike an upright.

Lovely sleight of hand by Steffan Jones almost opened Ulster up, then Faletau and Dan Lydiate combined at the back of a scrum, but the gnarled Ulster defence with its three South Africans held firm.

But the Dragons tried again, and this time they succeeded. Faletau, Luke Charteris twice and Lydiate all made inroads and when the ball was recycled Matthew Jones picked out Tom Riley with a flat pass and the centre was over for a try which Matthew Jones converted.

Humphreys missed a penalty shot before Joe Bearman went on for Faletau to prolonged applause in the 62nd minute to make his final appearance for the Dragons.

And Bearman showed a typical touch as he put Riley clear, but the centre’s kick through just eluded Steffan Jones.

Dragons captain Tom Willis made his first appearance for months after a thumb injury before Matthew Watkins also went on for his last game for the region.

But the closing stages were confined to midfield, Ulster content to hold what they had and the Dragons unable to add to their total.

Newport Gwent Dragons: S Jones, A Hughes, T Riley (M Watkins 70), P Leach, A Brew, J Tovey (M Jones 16-28, 42), W Evans (J Evans 76), P Price (H Gustafson 62), L Burns (T Willis 69), D Way (B Castle 71), L Charteris (captain), A Jones (A Coombs 71), D Lydiate, T Faletau (J Bearman 62), G Thomas.

Scorers - try: T Riley; conversion: M Jones; penalties: M Jones, J Tovey.

Ulster: A D’Arcy, C Gilroy, D Cave, N Spence, S Danielli, I Humphreys, R Pienaar, T Court, R Best (captain), D Fitzpatrick (P McAllister 57), J Muller, D Tuohy (T Anderson 71), P Wannenburg, R Diack (T Barker 66), C Henry.

Scorers - tries: N Spence (2), P Wannenburg; conversion: I Humphreys; penaltiy: Humphreys.

Referee: Alan Lewis (Ireland).

Attendance: 5,062.

Argus star player: Gavin Thomas.