PENLAN outscored hosts Brynaman by two tries to one in division three south west but were pipped 19-17 by the Amman Valley men.
Brynaman roared into a 13-0 lead after 20 minutes, though Penlan hit back to lead 14-13 at half-time.
The home side landed two penalties to Penlan's one in the second half as they just about did enough to claim victory.
Lock Kurt Velardo and Penlan's man of the match, No. 8 Ian Scrine, crossed for the Swansea side and fly-half Steven Davies landed both conversions and a penalty.
Centre Paul Taylor got Brynaman's only try, and Dafydd Jones added the conversion and four penalties.
The result leaves Penlan fourth and Brynaman second, although Brynaman were unable to close the 25-point gap on runaway leaders Ystalyfera, who won 23-8 at fifth-placed Pencoed.
After a close first half, after which they led 13-8, Ystalyfera added two unconverted tries to close out victory.
Centre Ashley Carter, No. 8 Steffan Jones and scrum-half Tom Barry crossed, with fly-half Gareth James adding a conversion and two penalties.
Glyncorrwg moved up to eighth thanks to a 14-8 win at home to second-from-bottom Morriston.
The Swansea side led 8-6 at the interval but a try by skipper and No. 8 Anthony Davies and a penalty by full-back Josh Thomas, adding to his two in the first half, sealed victory for the Afan Valley men.
Maesteg Celtic beat local rivals Pontycymer 13-8, while Taibach ran in eight tries in their 55-12 home win against Resolven.
With just four minutes on the clock, centre Matthew Phillips evaded several tackles to run in from 35 metres for Taibach's first try, with fly-half Mike McSweeney converting.
The next came from a scrum on halfway and after slick handling from No. 8 Alex Holland and McSweeney, centre Neil Gadd outpaced defenders and ran in.
Resolven responded with a pushover try by No. 8 Richard Davies, but Taibach's third try quickly followed when Matthew Phillips made a break and wing Matthew Hare sprinted over. McSweeney converted, and then kicked a penalty in injury time for a 24-5 half-time lead.
The Tigers' dominance continued in the second half, with tries going to wing Gareth Williams and hooker Rhys Whelan, the latter coming after a fine move involving Craig Clement, Craig Whelan and second row Ashley Jones.
Resolven flanker Craig Pritchard was awarded a try from a driving maul, with full-back Nathan Davies converting, before Taibach prop Damien David did well to stretch over the line for a try.
The seventh home try came from centre Gadd, who beat several men following a breakout from their own 22, and in the final play of the game Matthew Phillips raced away from 25 metres for his second touchdown.
Mid-table Neath Athletic beat bottom-placed neighbours Bryncoch 39-14, scoring six tries in the process.
Wing Josh Ebbitt and centre Chris Weightman got two each, and scrum-half Tom Griffiths and replacement prop Chris Partin also crossed. Fly-half Adam Rowlands converted three of them and also put over a penalty.