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 U20 duo Leon Brown and Lloyd Lewis face a busy couple of weeks ahead. Not only will they have a Junior World Championship to take part in, they are both sitting A Level exams during the competition.
Wales U20 face a tough group in the Junior World Championship with France, England and Japan lying in wait but Attack coach Jason Strange and back rower Tom Phillips are looking forward to the campaign ahead.
Angus O'Brien has quickly settled into the Wales Sevens squad after solid performances in Hong Kong and Japan. With two rounds remaining in Glasgow and Twickenham on the World Series, WRU TV's Graeme Gillespie chats to the rising star.
Wales winger Luke Morgan has established himself as one of the deadliest finishers on the Sevens World Series. WRU TV's Graeme Gillespie catches up with him on the eve of this weekend's round in Glasgow.
All roads lead to Cardiff on Sunday for the SSE SWALEC Finals Day at the Millennium Stadium. Cambrian Welfare tackle Ystradgynlais in the Bowl final, Ystrad Rhondda play Newcastle Emlyn in the Plate final while defending champions Pontypridd face Bridgend in the Cup final.
WRU Chief Executive Roger Lewis, Deputy Minister for Culture, Sport and Tourism Ken Skates and WRU Chairman Gareth Davies earlier this week launched a new competition in conjunction with the WRU unveiling its archive room.
Welsh players and management joined Deputy Minister for Sport Ken Skates at the Pierhead Building, Cardiff Bay earlier this week to reveal the Union's pioneering school-club hub initiative has been so successful the project will now almost double the scale of the original project.
The Scarlets, Newport Gwent Dragons, Cardiff Blues and the Ospreys look ahead to Judgement Day III which sees the Blues take on the Ospreys (2.30) and the Dragons tackle the Scarlets (4.45pm) at the Millennium Stadium tomorrow afternoon.
Ystradgynlais and Ynysddu played out a titanic struggle at Taffs Well in the SSE SWALEC Bowl semi-final. At the end of the game neither team could be separated after a 15-15 stalemate but Ystradgynlais go through on try count.