Gavin Evans pounced for a opportunist try as Cardiff Blues held on for a hard-fought victory over London Irish.
The Blues were already out of the LV=Cup but they produced a committed performance as Phil Davies' men followed the lead of Wales Under-20s with a victory over Irish opposition.
Tom Homer kicked the visitors in front but he failed to control Rhys Patchell's kick as Evans capitalised.
The Blues made a bright start in the difficult conditions at the Arms Park, with both Patchell and Michael Paterson threatening on the counter attack but it was the Exiles that took the lead thanks to the boot of Homer.
Cardiff fought back and they surged into the lead as Homer appeared to flap at Patchell's long kick to allow Evans to snatch an opportunist score.
Patchell slotted the extras to hand the Blues a 7-3 lead at the break.
The Exiles came flying out of the blocks in the second-half and Guy Armitage almost burst clear for an early try but the Blues scramble defence was up to the task.
Homer cut the deficit to a single-point after Cardiff were penalised at the scrum on 54 minutes.
But again the Blues rallied with Patchell and captain, Evans and Jason Tovey at the fore. They twice came close to crossing the whitewash but Irish held on.
Patchell missed a second shot at goal on 60 minutes but he quickly made amends to restore the slender advantage.
The English club dominated exchanges at the death but Phil Davies' men defended heroically to secure the win.
Wales Head Coach Rob Howley talks to WRU TV's Sebastian Barrett about the 36-man squad he has just named for the forthcoming Under Armour series, which includes two uncapped players, Ospreys duo Sam Davies and Rory Thornton.
Head coach Rowland Phillips is deligthed he can now call BT Sport Cardiff Arms Park home for his Wales Women's side, who launch their international season next month with games against Scotland and UK Armed Forces in the heart of the capital city.
Wales Sevens star Sam Cross has put his home town club of Brynmawr on the map after winning a silver medal at the Rio Olympics with Team GB. His club have now honoured him by naming their players bar after him, as WRU TV discovered at the official launch, recently.
One of the newest members of the Principality Premiership, Bargoed admit it's proving to be a steep learning curve at the highest level, but are determined to become a force to be reckoned with. WRU TV visited the club last weekend when they took on Llanelli.
Table-topping Aberavon travel to north Wales to tackle RGC 1404 as both teams defend unbeaten starts to the season in the Principality Premiership. WRU TV's Graeme Gillespie visited the Wizards to see how their preparations were going for the game of the weekend.
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.