Bonymaen shocked Carmarthen Athletic to win 14-13 at Five Fields and move off the bottom of Division One West.
Winger Robert Jones scored Bonymaen's only try, with Richard Cunniffe kicking their other nine points with two penalties and a drop goal.
Town rivals Carmarthen Quins faired much better, winning 32-6 at Cwmllynfell to extend their unbeaten run and remain top of the table.
In light of Bonymaen's win, Dunvant are now eight points adrift at the foot of the table following their 75-0 thrashing at second-place Tonmawr.
The Pitmen ran in 13 tries, with Ryan Baylis standing out as their hat-trick hero. He crossed three times during an emphatic victory, with Ben Davies going over twice as one of nine other Tonmawr try-scorers.
Whitland moved third after beating Llangennech 45-3, posting six tries including two for Lee Glanville.
Corus ran in four tries to beat Narberth 34-10, with full-back Rhys Williams kicking 11 points for the Steelmen. Felinfoel change places with Maesteg in sixth after they won 19-18 at Llynfi Road.
Merthyr stay top of Division One East with a predictable sixth victory of the camapign at bottom side Newport Saracens, who remain without a win so far this season. Full-back Adam Williams scored two of his team's six tries in the comfortable 43-7 win.
Newbridge remain second following their 33-16 success against Llanharan following two tries from Ceri Young.
Bargoed racked up a bonus point in their impressive 30-5 away win at Penallta keeping them hot on the trail of the top two.
Beddau lifted themselves clear of relegation with a 41-16 victory over Rumney. Matthew Evans scored two tries for Beaddau, the others came from Slater, Cleverly and Adams while Rhys Truelove racked up an impressive 16 points from the boot.
Gareth Price kicked three penalties to secure a 14-10 win for Blackwood over strugglers Ystrad Rhondda while Uwic scored four tries to beat Caerhilly 29-23 in a thrilling game at Virginia Park. Uwic held a convincing 17-5 lead at half-time but were left holding on at the end thanks to some reliable kicking from the boot of Colin Ashton.
The Half a Game initiative is currently sweeping across Wales and proving a major success. The scheme aims to give every young player at least half a game every weekend. WRU TV recently visited a festival in Narberth where clubs have fully embraced the initiative.
Both Bargoed and Swansea were seeking their first win of the Principality Premiership season this afternoon. It proved a fruitful day for the hosts - not only did they win, but Bargoed claimed a try bonus point.
Cardiff managed to keep their unbeaten record at home intact, but only just as Bridgend made them work extremely hard before the Blue and Blacks secured a hard fought Principality Premiership win at the BT Sport Arms Park last night.
Former Wales back row Andy Powell gives a guided tour of The Wern, home of Merthyr RFC, who are determined to prove a lot of people wrong and make their mark in their first season in the Principality Premiership.
Wales Sevens head coach Gareth Williams looks back on the Rio Sevens success where he helped GB win silver. He believes the successful campaign is a huge boost to his Welsh squad as they prepare for another World Series, as WRU TV's Graeme Gillespie discovers
British and Irish Lions head coach Warren Gatland will be heading back home to take on the All Blacks next year where for him, success for 2017 is all about going to New Zealand and winning a Test Series.
Last week all roads led to Eugene Cross Park where defending champions Ebbw Vale hosted this season's launch of the Principality Premiership. WRU TV's Graeme Gillespie was there to capture the thoughts of Damien Hudd, captain of Ebbw Vale, and WRU Head of Performance, Geraint John.
Llandovery made it three in a row when they defeated Aberavon in the final of the National Foster's 7s at BT Sport Cardiff Arms Park on Sunday. On another eventful day of sevens, Newport claimed the Plate and the Dragons won the women's crown
Last week saw Cardiff welcome players from around the world for the 21st Golden Oldies Festival. The tournament features players over 35 years of age, and this year's event saw a select few represent the WRU in a 'friendly' against the Wooden Spoon.
Wales Under 18 captain Callum Bradbury is delighted to have seen his side claim a narrow 18-17 victory against a strong SA Schools 'A' side to end the three-match Under 19 International Series in South Africa on a high note.
The Wales U18 squad spent an emotional day in the drug-riddled townnship of Hout Bay. Hout Bay Warriors President Fred Johannes said the visit was 'the talk of the town' and will dream about the day everyday for the rest of his life.
RGC 1404's new head coach Mark Jones is hoping to build 'something special' in north Wales and is already looking forward to the development region participating in the Principality Premiership for the very first time.