Bristol followed up three wins out of their last four Guinness Premiership outings with their best performance of the season to beat the Scarlets 18-11 in their opening EDF Energy Cup game at the Memorial Stadium on Sunday.
The home side made eight changes from the side that beat Leeds last weekend in the Premiership and included England World Cup scrum-half Shaun Perry in his first game for his club this season.
Skipper Matt Salter was rested so flanker Joe El Abd came in at openside flanker to lead the side while the Scarlets made six changes, with Irish international flanker Simon Easterby back to lead the side having returned from World Cup duty.
The Magners League side, losing finalists in this competition two seasons ago, included young fly-half Rhys Priestland who kept his place in front of Welsh international half-back Stephen Jones who was on the bench.
It was Priestland who put the visitors in the lead after just five minutes with a 40- metre penalty from in front of the posts but Bristol were quickly back on level terms as fly-half David Hill slotted the ball between the uprights from the same range.
The Scarlets looked set to score a try in the right corner through second row Vernon Cooper but, after consulting with the television video match official, referee Tim Hayes ruled he had put a foot in touch after a Perry tackle.
The referee exerted his control of the game as he punished any dissent after his decisions as he marched Bristol back 10 metres and into their own half.
Priestland was unable to find his target with his next kick from close to the right touchline.
Perry gave an awkward pass to wing Lee Robinson who juggled the ball before embarking on a swerving run for the line but full-back Morgan Stoddart dragged him into touch just short of the line.
But Robinson was rewarded for efforts minutes later from a move started from a scrum in front of the posts.
The ball was worked out for Robinson to step inside the full-back to score but Hill was way off target with the conversion.
Bristol increased their lead on the half hour after opting for a series of scrums close to the line when awarded penalties.
Finally they set up a driving maul with number eight Andrew Blowers getting the touchdown to which Hill to added the extras.
Just before the interval Scarlets wing Matthew Watkins burst 45 metres but centre Rob Higgitt raced back to pull off a try-saving tackle just short of the line.
Then Bristol managed to defend their line to go into the break 15-3 up.
Jones, on as a half-time replacement for Priestland, and Hill exchanged penalties in the opening five minutes of the second half.
The Scarlets then applied pressure on the Bristol line but again the defence was solid.
With 15 minutes still to play Bristol were reduced to 14 men with centre Neil Bew yellow-carded for an infringement at the tackle.
The Scarlets, despite being camped in the Bristol 22, failed to capitalise on the extra man.
On the stroke of full-time Stoddart, taking a flicked pass from centre Regan King, crashed over the line for the Scarlets' only try of the game but Jones was unable to convert from out wide.
Tries: Robinson, Blowers
Pens: Hill 2
For the Scarlets:
Pens: Priestland, Stephen Jones
Yellow card: Brew (65, Bristol)
Bristol: 15 Tom Arscott, 14 Lee Robinson, 13 Neil Brew, 12 Rob Higgitt, 11 Craig Morgan, 10 David Hill, 9 Shaun Perry, 8 Andrew Blowers, 7 Joe El Abd (c), 6 Nathan Budgett, 5 Sean Hohneck, 4 Gareth Llewellyn, 3 Darren Crompton, 2 David Blaney, 1 Alex Clarke
Replacements: 16 Scott Linklater, 17 Ray Hogan, 18 Dave Attwood, 19 James Phillips, 20 Haydn Thomas, 21 Jason Strange, 22 Luke Eves
Scarlets: 15 Morgan Stoddart, 14 Mark Jones, 13 Regan King, 12 Gavin Evans, 11 Matthew Watkins, 10 Rhys Priestland, 9 Dwayne Peel, 8 Dafydd Jones, 7 Johnathan Edwards, 6 Simon Easterby (c), 5 Adam Eustace, 4 Vernon Cooper, 3 Deacon Manu, 2 James Hayter, 1 Phil John
Replacements: 16 Bruce Douglas, 17 Matthew Rees, 18 Scott MacLeod, 19 Alix Popham, 20 Liam Davies, 21 Stephen Jones, 22 Dafydd James.
Referee: Tim Hayes (Wales)
Touch judges: Phil Fear (England), Huw David (Wales)
Television match official: John Burtenshaw (England), Geoff Warren (England)
Assessor: Paul Bridgman (England)