Blackwood Bulldogs put in an outstanding second half performance to overcome Cardiff Demons 28-20 to qualify for the Welsh Grand Final at the Brewery Field in Bridgend next Sunday.
The final, against Valley Cougars, kicks off at 1pm and will be played before Celtic Crusaders clash against Leigh Centurions in National League One.
The semi-final was the first time that Cardiff Demons had been beaten by more than six points all season, but the game was ruined as a spectacle for the fans as the match officials refused to let the game flow, blowing up for every minor infringement.
Gareth Jones had an opportunity to give Demons an early lead with a penalty after Blackwood were penalised in the play-the-ball but the kick went centimetres wide.
However he made up for it on 14 minutes when he kicked a successful goal from in front of the sticks following another infringement.
It was Blackwood who scored the first try when Anthony Symonds set up Paul Emmanuelli to go over in the corner.
Cardiff levelled things five minutes later through another Jones penalty goal.
Blackwood had an opportunity to regain the lead five minutes before the interval but Byron Williams was held up over the line by Marcus Edwards.
However they made up for it in the tenth minute of added on time in the first half when Gareth Price dived in under the sticks with Emmanuelli converting.
The second half was all Blackwood