The Scarlets took fourth place in the Magners League on Thursday with a battling 17-12 win over the Ospreys at Stradey Park, leaving the Neath/Swansea region well off the League pace in the process.
In a gripping contest played out in front of a festive sell-out crowd, tries in each half by flanker Gavin Thomas and replacement centre Nathan Brew sealed a much-needed victory for the home side.
The Ospreys pressed strongly in the closing stages, but all Lyn Jones' men had to show for their efforts was four penalties from the boot of Wales fly-half James Hook.
With only two wins from eight league encounters, the Ospreys' title challenge looks all but over this season as they turn their attention to the semi-finals of the EDF Energy Cup and the Heineken Cup.
As for the Scarlets, following their European tribulations, this morale-boosting victory revitalises their league challenge going into the new year with just four points separating them from leaders Leinster with a game in hand.
Both sides had gone into the match on the back of contrasting fortunes on the European front.
The Scarlets were desperate for any sort of victory after four straight defeats in the Heineken Cup, while the Ospreys were looking to maintain their impressive momentum of recent weeks.
Yet Jones' star-studded squad have struggled in the defence of their Magners League crown this season and with just two wins from in the competition this season they went into the match with their title hopes hanging by a thread.
It all made for a charged atmosphere in front of a full house at Stradey and the promised fireworks appeared from the start when former Scarlets favourite Mike Phillips was sin-binned inside two minutes.
Phillips was shown yellow for a late challenge on Wales colleague Mark Jones and it gifted the Scarlets all the early momentum.
However, a pumped up home side failed to take advantage.
Stephen Jones struck the upright with the ensuing penalty before Wales rival Hook landed the first points of the match as Phillips returned to the fray.
The lead did not last long though as the Scarlets' under-fire pack paved the way for the opening try of the match.
Strong driving work from a close-range line-out put the Ospreys on the defensive and flanker Gavin Thomas made the most of a rare blindside opening to dash over for the score.
Jones converted, only for Hook to reduce the advantage on 31 minutes after one of the few Ospreys attacks of a stirring first half.
A third Hook success, after the Scarlets had again been penalised in front of their posts, made it 9-7 at the interval and left the home side down to 14 men with lock Vernon Cooper given 10 minutes on the sidelines.
It needed a superb try-saving tackle by Stephen Jones to halt wing Aled Brew straight from the restart as the Ospreys pressed strongly.
The Wales fly-half then struck his first penalty before the Scarlets claimed their second try on 49 minutes.
It came from a mistake from the Ospreys and international back-rower Jonathan Thomas who lost possession just outside the 22. The ball was moved quickly to replacement Brew and he showed good strength and pace to outstrip the defence to score.
Jones' conversion made it 17-9 and the Scarlets were sniffing blood.
Hook reduced the arrears with his fourth penalty and then galloping Wales lock Alun Wyn Jones was held up by some despairing cover defence with 10 minutes remaining.
The Ospreys surged forward powerfully for the crucial score late on, but centre Andrew Bishop knocked on with the line in sight and despite 10 minutes of stoppage time stubborn defence ensured a welcome home triumph.
For the Scarlets:
Tries: Thomas, Brew
Cons: Stephen Jones 2
Pen: Stephen Jones
For the Ospreys:
Pens: Hook 4
Yellow cards: Phillips (2, Ospreys), Cooper (38, Scarlets)
Scarlets: 15 Morgan Stoddart, 14 Mark Jones, 13 Regan King, 12 Gavin Evans, 11 Nathan Brew, 10 Stephen Jones, 9 Dwayne Peel, 8 Alix Popham, 7 Gavin Thomas, 6 Simon Easterby (c), 5 Scott MacLeod, 4 Vernon Cooper, 3 Deacon Manu, 2 Matthew Rees, 1 Iestyn Thomas.
Replacements: 16 Bruce Douglas, 17 James Hayter, 18 Adam Eustace, 19 Dafydd Jones, 20 Gavin Cattle, 21 Ceiron Thomas, 22 Jonathan Davies.
Ospreys: 15 Lee Byrne, 14 Nikki Walker, 13 Mark Taylor, 12 Andrew Bishop, 11 Aled Brew, 10 James Hook, 9 Mike Phillips, 8 Ryan Jones (c), 7 Ben Lewis, 6 Jonathan Thomas, 5 Alun Wyn Jones, 4 Ian Gough, 3 Adam Jones, 2 Richard Hibbard, 1 Duncan Jones.
Replacements: 16 Huw Bennett, 17 Cai Griffiths, 18 Lyndon Bateman, 19 Tom Smith, 20 Justin Marshall, 21 Shaun Connor, 22 Jonathan Vaughton.
Referee: Nigel Owens
Touch judges: Nigel Whitehouse, Jon Mason
Television match official: Hugh Watkins