Waunarlwydd had prop Gareth Richards red-carded in the second minute, but still amazed leaders Dunvant by gaining a 19-18 away win. Gary Diamond came off the bench and was a hero, while fly half Lee Jones had his first match back since breaking a finger against the same opponents earlier in the season and he scored a conversion, two penalties and two-dropgoals. Centre Matthew Wright scored a vital try.
Cwmllynfell joined Dunvant on 31 points after a last-gasp 12-11 win over Corus, while young flanker Rhys Shellard is following in the family tradition after gaining his fourth try in five matches for Abercynon in the East.
Wing Dan Bowcott joined in the try-scoring and Matthew Turner kicked five points as the 'Cynon' defeated Llantrisant 17-0, while Dinas Powys jumped up with a 44-5 beating of Penygraig with flyhalf Lloyd Smith getting one of the seven tries and kicking nine points.
Merthyr pulled off an important 10-3 win at Rhymney thanks to a brace of tries by wing Gethin Thomas against a Barry Davies penalty and are joined at the top by Builth Wells, who won 13-0 at Ystrad Rhondda.
Glyncoch have had a remarkable past couple of seasons, having lost just once in the last two seasons. Their fine form has been capped by claiming the South Central Division 5 crown of the SWALEC League.
With two rounds of the HSBC Sevens World Series remaining, Wales head coach Paul John has sprung a few surprises for this week's penultimate round in Glasgow. And there's still plenty to play for with World Cup spots on the line.