An 11-minute blitz, and stoic defensive effort, proved more than enough for Collegians to claim the first berth in the grand final on Saturday.
De La Salle started the major semi-final strongly with the opening try to Trentham Petersen in the eighth minute, with Collegians taking another 10 minutes to find a response through a determined Blake Dowel.
It made it an even contest through 20 minutes, but tries to Callum Gromek and Campbell Rubie in the 11 minutes before the break proved the telling stretch of the contest.
After looking dangerous early, De La couldn't buy a point in the second half despite a mountain of opportunity in the face of what proved an immovable red and black wall.
Sapped from the defensive effort, the Dogs could only manage a late penalty goal through Max Devlin in the second stanza, but it took nothing away from emphatic nature of the victory.
De La coach Luke Manahan was left with more headaches than just the result, with lock Jacko Stewart (high tackle) and Jack Williams (dangerous throw) ending the match on report.
Mitch Jennings says:
"Truly faultless performances are rare in rugby league, but Collegians went mighty close with this effort. Wore an early onslaught for just one try and didn't concede again in one of the best defensive performances of recent times.
"Peter Hooper's side has an unmatched ability in this competition to not just absorb pressure, but counterpunch as they did superbly on Saturday.
"Fullback Callum Gromek is a truly special talent and shapes as the key top-up ingredient to a hardened side choc-full of experienced heads that's claimed the last two crowns.
"They've claimed three of the last four premierships, but the new test will be carrying a weight of favouritism into the decider they've never had to bear through a this dominant era.
"It'll be back to the drawing board for De La Salle, who had enough ball and field position to win three games in the second half and couldn't strike a blow.
"They could be tested further on that score, with key half Jack Williams sure to attract scrutiny for the lifting tackle on Collies prop Josh Dowel that landed him on report late.
"Had been up for a long time heading in on seven straight wins, so perhaps better to cop the reality check in week one than on the biggest day."
Thirroul look to be hitting form at the right time after seeing off Wests in the minor semi-final to notch the club's first post-season win since 2018.
A double to halfback Tarje Whitford either side of halftime was the telling factor for a Butchers side at full strength for the first time since round four.
Winger Jye Hitchcox very nearly proved the unlikely hero for the Devils, with a hat-trick of tries and multiple line breaks - including one at the death that very nearly snatched a late victory.
It was as mighty a performance as it gets from a winger, but it wasn't enough as a sluggish start from the Devils proved too much to overcome.
Thirroul now head for the prelim, while Wests head for Mad Monday at the end of a gruelling campaign.
Mitch Jennings says:
"Jarrod Costello hinted at it post-game, there's just a feeling about this Butchers side and timing.
"Being well out of top-two reckoning has let Costello gear all efforts to timing a late grand final run and his side cleared the first hurdle in gritty, if not clinical fashion.
"Experienced heads stood up, but the most telling fact out of the game was the mature performance of Tarje Whitford in the No. 7. Two tries and solid kicking game amounted to finals coming-of-age performance from the reigning Paul McGregor Medalist.
"Likewise, emerging forwards Kaleb Hocking and Ammon Cairney are seasoned first-graders, but the win also amounted to their arrival as finals-proved performers.
"It was an error-riddled game from both sides, and Thirroul will need to be much better to upset De La Salle in the prelim. If they can avoid being blown away early, they'll like their chances in a war of attrition.
"It's an underwhelming exit for the Devils who, despite not talking about extensively, had hearts set on redemption after a controversial defeat in last year's grand final.
"Were only one win off a top-two finish, but looked noticeably weary as the season reached the back end. Were in it right to the end, but didn't have the petrol in the tank to pull the trigger after injury-plagued campaign."
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