Cardiff Blues clinched the inaugural Syft International Challenge as they crossed for seven tries against Uruguay at the Arms Park.
Los Teros drew first blood in the capital before John Mulvihill's side took control of the encounter - they led 12-7 at the break thanks to tries from Alun Lawrence and Max Llewellyn.
Three more tries were added in a second-half purple patch with Ethan Lewis, Ioan Davies and Harri Millard all touching down.
Uruguay threatened a comeback with two tries in two minutes from Felipe Berchesi and Facundo Gattas but the victory was secured when Rhys Gill cantered over from a Dan Fish offload.
The Blues had not faced international opposition since losing to Australia in 2010, but the fixture rejuvenated a long tradition of touring teams visiting the Arms Park.
For Uruguay, it was the beginning of their preparations for the 2019 Rugby World Cup. Los Teros qualified comfortably for the global showpiece and were drawn in the same pool as Wales.
The South American-outfit now go on to face Ulster on Friday night.
For the Blues, there is now a two weekend break in fixtures before three weeks in a row on the road against Glasgow and Ulster in the Guinness PRO14 and Saracens in the Heineken Champions Cup.
They return to Cardiff Arms Park on December 15, for the return European clash with the English champions.
The opening exchanges at a drenched Arms Park were littered with errors but Uruguay soon took territorial control.
After kicking a penalty to the corner, Los Teros soon claimed the opening try with second-row Ignacio Dotti powering over from close range. Federico Favaro soon converted but it did not take the Blues long to respond.
They quickly reclaimed possession and worked their way into the Uruguay half, with Alun Lawrence hitting a short ball from centurion Fish and skipping past two defenders to score.
Matthew Morgan added the extras to level the scores and the free-flowing nature of the game continued as Cardiff Blues soon added a second.
It all began with a Lewis Jones snipe and following fine interplay between Lawrence, Max Llewellyn, Rhys Carre and Liam Belcher, centre Llewellyn finished in the corner.
Morgan pushed his effort narrowly wide but the try had given his side the advantage in increasingly difficult conditions.
Uruguay threatened to hit back when Santiago Arata broke down the fringe and kicked ahead for Favaro but Millard recovered to save the day.
Both sides enjoyed further opportunities, notably when Rhys Carre burst through midfield and raced into the Uruguay half and when he combined with prop partner Keiron Assiratti.
But on both occasions play broke down and the score remained 12-7 at the interval.
Wales' Capital Region claimed third try of the evening shortly after the restart as the pack rumbled over from a driving lineout to allow Lewis to dot down.
They could have had a fourth when Cam Lewis raced after a kick through from Harri Millard but he was taken out as early as he attempted to collect.
Favaro was subsequently send to the bin but referee Adam Jones did not award the penalty try, adjudging that the wing still had plenty to do in the slippery conditions.
However, they required no second invite as they scored from the ensuing penalty with Ioan Davies collecting a Fish cross kick for a try on his full debut.
The home side continued to run riot as the floodgates opened with Millard the next to score. Quick hands from Llewellyn and Fish releasing the centre, who dummied past one defender before bundling through another for a fine try.
Felipe Berchesi responded with a try for the visitors, which he then converted to give his side hope of a comeback and one minute later they were right back in it as Facundo Gattas crashed over.
Berchesi was once again on target to cut Cardiff Blues' lead to 10 and set up a tense finale.
However, Fish once again was the insigator for the hosts' sixth try, as his offload released experienced prop, Gill, for his first score in Cardiff Blues colours.
In the final play of the game, a destructive scrum from the host saw referee Adam Jones run under the posts for a penalty try.