The Blues put one over on the Ospreys in last night's penultimate pool game in the WRU Regional under 18 Championship at Jenner Park in Barry.
However, their 25-22 success in front of a record attendance for the competition - 1300 - does not affect the overall standings in the table.
In fact with the two sides having performed so well in the opening three months of the season, they will meet once again at the end of next month in the final at Llandovery.
With that game in mind, the Blues were understandably keen to strike a physcological blow. And they achieved that courtesy of tries from captain Jake Thomas, Christian Dacey and Lloyd Williams and three conversions and a long range penalty from Joe Deacon.
They led 15-12 at the interval with high performance manager Gafyn Cooper delighted with another excellent performance.
He said, "It was another great night for the boys. The staging of the game could not have been better and the crowd was far and away the biggest we have played in front us.
"They are a good side and made life really difficult for us, but we held on and Joe Deacon's penalty from half way earned us an excellent win."
In the other game, the Dragons recorded a 34-10 win over the Scarlets at Abertillery Park.
Season Ticket holders at Cardiff Blues are reminded that they gain FREE entry to the British & Irish Cup pool fixtures this season - starting with Saturday's home fixture against Nottingham Rugby at BT Sport Cardiff Arms Park (kick-off 2.30pm).
Teenage Cancer Trust will be collecting for valuable funds at BT Sport Cardiff Arms Park on Saturday afternoon ahead of our British & Irish Cup fixture with Nottingham Rugby (kick-off 2.30pm). Ahead of the game, we take a closer look at the charity and discover how they are making a difference...
Cardiff Blues suffered a first defeat of the season in the European Rugby Challenge Cup as a second half burst of tries from Harlequins saw the English side claim victory at BT Sport Cardiff Arms Park.