Loughor are within a point of Division Two West leaders Builth Wells after they beat Bridgend Athletic
With Builth Wells' trip to Cwmavon being postponed, the second and third placed clubs had the chance to play their game in hand at Villa Field.
Hosts Loughor ran out 15-13 winners, but needed a late penalty to do so. Ospreys academy centre Ben John put the winning kick over on 75 minutes.
Elsewhere BP Llandarcy scored three tries in their 28-11 win at Mumbles, whilst Kidwelly beat Gorseinon 25-15 on Boxing Day.
Pontyberem kept their winning run going at the top of Division Three West, picking up at slender 27-21 win over mid-table Crymych. Two tries from Phil Rose and a further score from Richard Thomas ensured that Pontyberem go into 2009 with their 100 per cent league record in tact.
Shane Williams' first club Amman United picked up their first win of the season, and they did so in style with a six try 37-12 win at Tumble to move off the bottom of the table.
This try tally was only bettered by Laugharne, who scored ten in their 71-15 win over Llanelli Wanderers.
Cardigan beat Newcastle Emlyn 18-6 in a local derby, Aberystwyth defeated Lampeter 24-10 and Haverfordwest won 17-11 at Llanybydder.
Division Three South West table toppers Tondu saw off Glynneath 63-9, with Dean Thomas scoring 23 points including one of the host's nine tries.
Second place Aberavon Quins kept up the pressure by recording a winning bonus point in beating Maesteg Celtic 32-14.
Maesteg Quins defeated Kenfig Hill 30-12 and Skewen breezed past Tonna 50-0.
Wales and Ospreys back row James King, who came through the North Wales age grade system, nominated North Wales Regional Community Rugby Manager Marc Roberts, in the WRU's 'Diolch' initiative where squad players thanked those who played a part in their rise to the top.
Beating Merthyr has boosted Carmarthen Quins hopes of reaching a top eight spot in the Principality Premiership. Quins captain Haydn Pugh is delighted with his team's progress and is determined that everyone from the Under 6s through to the senior team, enjoys the ride.
When the Wales squad were asked to nominate individuals who played a big part in their early playing days, Wales and Dragons full back and wing Hallam Amos thought of his former Monmouth School rugby coach John Bevan.
Sam Cross and Luke Treharne have been named as co-captains of the Wales Sevens side as head coach Gareth Williams names his 12-man squad to play in the first leg of the HSBC World Series in Dubai next weekend.
Bedwas head coach Steve Law and players Nicky Griffiths and Alun Rees extol the virtues of the close knit club as they prepare to host third place RGC 1404 - who are one place head of them on the Principality Premiership points table - on Saturday.
Many of the Wales squad have said Diolch (thank you) to someone who played an important part in their early playing days by nominating them to be invited to the Wales v South Africa match. One person, Gowerton Comprehensive geography teacher Mr Dean Mason was nominated by two of his former pupils, Dan Biggar and Sam Davies.
The second WRU disability rugby pilot has been delivered, this time in Caerphilly schools, culminating in a festival at the Caerphilly Centre of Sporting Excellence, Ystrad Mynach tomorrow. Plans are in place to set up a Disability Rugby Club in Newbridge to provide long-term playing opportunities.
WRU TV: Hear from inside the Wales camp as Neil Jenkins discusses this weekend's clash with South Africa and how the squad are looking to put in a strong performance to round of the 2016 Under Armour Series