Penarth returned to the top of Admiral League Division One with a 14-8 win over Barry.
The Vale derby also marked the Bears' first home game since the fire which gutted the Athletic Club last month.
George Roberts and Rhys Mottram crossed for the hosts who are just a point clear of title rivals St Albans, who now have a game in hand, while Barry remain third bottom and six points above the drop zone.
A couple of crucial moments decided this hard-fought derby fixture in Penarth’s favour - with one missed tackle and one fortuitous bounce leaving the Bombers the result might so easily have gone the other way.
Penarth completed the double over Barry, but the Bears were mightily relieved as an excellent defensive display by the Bombers held the hosts’ much-vaunted attack, which has been scoring tries for fun this season, in check.
Barry were set up initially to blunt the threat, with a mobile back five in the scrum stopping the danger out wide. Penarth rarely threatened down the flanks, but when they did, Barry generally snuffed out the attack and produced some excellent turnovers in the process.
But equally, Barry rarely really threatened in the Penarth half, opting to kick at times when keeping possession might have proved more rewarding. Owen Rees had given the Bombers the lead with a ninth-minute penalty, but they were unable to build on it, despite the occasional fluid attack.
Barry head coach Mike Morgan had mixed emotions after the game: "Coming to Penarth, a top table team, and to come away with a (losing bonus) point, is a positive," he said.
That, and the excellent defensive performance he described as “two massive pluses for us. As players and coaches we got a lot right today."
“We can be proud of the way we stuck at it. But if only we had found a little bit of purchase in their half, if we’d only been a bit more clinical, and not been so eager. We should have settled into our game in their half and kept a bit more ball.”
Penarth went ahead in the 29th minute when a missed tackle let Roberts in for their opening try with Mottram converting.
There was nothing between the teams at the interval, but when the game slowed in the second half, Barry made changes up front and began to totally dominate the scrums and driving mauls.
Penarth’s anxiety was briefly stilled in the 66th minute when a kick ahead bounced badly for Barry, but perfectly for Mottram to score under the posts, and then add the extras. The relief on the sidelines was palpable.
When Barry struck back five minutes later - Alyn Evans finishing off a tap penalty move - and the gap closed to one score, the concern among the home camp became obvious once more with one of Penarth's coaches sent off for disputing a decision.
But Penarth held out, gaining possession with the last move of the game and swiftly booted the ball into touch to clinch the bragging rights and return to the summit of Division One East Central.
Penarth visit St Albans next Saturday for a top-of-the-table clash while Barry visit Abercwmboi.
Elsewhere, Cowbridge kicked off the New Year with a 19-13 win over Taffs Well in Division Two, while in Division Three, Dinas Powys beat Gilfach Goch 31-24 and Llantwit Major romped home to a 51-22 victory over Canton.
Next Saturday's fixtures
Division One East Central
Barry v Abercwmboi
St Albans v Penarth
Division Two East Central
Cowbridge v Pentyrch
Division Three East Central
Cilfynydd v Dinas Powys
Ferndale v Llantwit Major
Divsion Five East Central
Old Penarthians v Tref y Clawdd
Division Six East Central
Sully Sports v Bridgend Athletic II

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Draconians end Llantwit's unbeaten run
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