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.
As the countdown continues for RWC2015, Tournament Chief Executive Debbie Jevans visited the Millennium Stadium to discuss preparations for the eight matches and reveal the positive news that 100,000 tickets for games at the home of Welsh rugby have sold in the last seven days.
Jason Harries is targeting a first win on the World Series circuit this season with Wales. The series returns to action this weekend in Dubai where Harries is part of a team hoping to build from its efforts in round one in October.
Wales skipper Jevon Groves says his side have addressed a few points from Gold Coast and aim to 'hit the ground running' in the next two rounds of the World Series, kicking off with this weekend in Dubai before heading off to South Africa next week.
Wales Sevens manager Steff Thomas is hopeful his side can build from a quarter-final spot in the opening round of the World Series in Australia when his side take part in the forthcoming double header in Dubai and South Africa.