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.
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.
Kiama 52 def. Tech Waratahs 24
Shoalhaven created history while fellow finals bound Kiama and Avondale finished the regular Illawarra rugby season with big wins on Saturday.
But the Shoals were pushed all the way by an impressive Campbelltown Harlequins outfit in their history-making 16th straight win.
The reigning premiers have won all 16 games they've played this season, but they were pushed all the way by a gallant Harelquins outfit in their latest victory.
In fact it was 7-7 at halftime before the home-side Shoalhaven outscored Campbelltown 17-7 in the second half to run out 24-14 winners.
Will Miller's all-conquering Shoalhaven will now play Avondale next Saturday, with the winner of the Shoalhaven Rugby Club fixture progressing straight to the grand final.
Shoalhaven 24 def. Campbelltown Harlequins 14
Avondale 81 def. Bowral 7
Shamrocks 25 def. University 5
Stingrays of Shellharbour 26 def. Shellharbour Sharks 16
The Stingrays are the new kings of Shellharbour after downing the Sharks 26-16 at Ron Costello Oval on Sunday to secure the club its first ever first-grade Group Seven rugby league minor premiership.
Stingrays player-coach Tom Warner said the win was the biggest and best ever in the Stingrays history.
And Warner can take a lot of credit for ending the Sharks' 11-game winning streak, crashing over for two tries in his own team's seventh straight success.
Warner's second try saw the inspirational skipper accept a great pass from five-eighth William Heda and run 40 metres unopposed to score in the corner.
Warner was ecstatic after the match.
"It's unreal, full credit to the Sharks we were up 18-0 but they kept coming, which we knew they would, but we held strong," he said.
"It's a massive win for us. It is the first minor premiership for the club. The boys deserve this, full credit to them.
"It's probably the biggest game the two clubs have played in. That's a massive win. I bet we will see them again, it's a big confidence boost."
Gerringong Lions 26 def. Jamberoo Superoos 18
Nowra-Bomaderry Jets 66 def. Berry-Shoalhaven Heads Magpies 14
Milton-Ulladulla Bulldogs 40 def. Warilla Lake South Gorillas 28
Albion Park-Oak Flats Eagles 46 def. Kiama Knights 22
Cringila 3 def. Bulli 2
The Lions have ensured that they will start their Illawarra Premier League finals campaign at Crehan Park after overcoming a spirited Bulli outfit 3-2 on Sunday.
The win saw Cringila leap-frog up to second position over Wollongong Olympic, who could only settle for a 1-1 stalemate with Coniston at JJ Kelly Park.
The Lions and Olympic will now meet on Crini's turf in a qualifying final next weekend, while Cono jump up into fourth place and will host Bulli in an elimination final.
The two matches highlighted a dramatic last day of the regular IPL season. All six games were held concurrently on Sunday, with four contests set to have an impact on the make-up of this year's finals series.
In the end, the top five sides heading into round 22 booked their tickets to finals.
Wollongong United and Port Kembla had also remained outside chances of keeping their campaign alive, but they fell 2-1 and 4-0 to Albion Park and Helensburgh respectfully on Sunday.
While there was plenty happening across the league, Lions captain Peter Simonoski and his teammates were happy to savour their victory.
"It was a good hit-out for us today and now we have one eye set on the semi-final. We have a big game coming up against Olympic next week," Simonoski told the Mercury.
Coniston 1 drew with Wollongong Olympic 1
Albion Park 2 def. Wollongong United 1
South Coast United 7 def. Bellambi 2
Tarrawanna 2 def. Corrimal 1
Helensburgh 4 def. Port Kembla 0
Balgownie 3 def. UOW 0
Balgownie's win against University meant as much to the players as it did to those watching at Judy Masters Oval.
The Rangers capped off the season with a 3-0 win against UOW with many of its former legends in attendance.
The day was all about off the pitch more than anything, with Balgownie - the oldest running football club in Australia - hosting their annual 'old boys day'.
The event had a different element to it with this being 140 years since the club was established.
Rangers striker Jesse French - who scored the side's final goal of the season - said playing in front of the club legends spurred them on.
"Great way to finish the season. Three goals, a clean sheet on old boys day. It was sick," he said.
"That was the most up for it we've been for a long time. It was a massive turnout and with 140 years [of the club] we spoke about it during the week that we wanted to give everyone that came here a big performance. All three grades with the win, we couldn't do much more."
Oak Flats 2 def. Fernhill 0
Picton 1 def. Thirroul 0
Unanderra 1 drew. Shellharbour 1
Warilla 4 def. Berkeley 2
Blacktown 1 drew. Wolves 1
The Wolves dominated proceedings against the defending grand final winners Blacktown but could not take away all three points.
But despite not walking away with the win, Wolves coach David Carney said his team continued to impress in the draw, even gaining praise from experienced NPL NSW coach Mark Crittenden.
The Wolves took the lead in the first half through Takumi Ofuka before having a number of chances to win the game. However a long throw in in the 89th minute caused heartbreak for Carney's side with Carlos De Oliveira netting the equaliser.
Whilst he was disappointed, Carney said there were again positives to take from the game and the season with one fixture left in the season.
"We could have been three or four up to be fair but to go to Blacktown away and pick up a point is a good effort. But it should have been three," he said.
"The lads were upset because we didn't win. That just shows how far we've come. To go to last year's champions and come to their ground and dominate them as even their coaching staff said to us that they were lucky to get a point and that we were really good and that says a lot.
"And he's an experienced coach so for him to say we dominated them is credit to the boys."
Northern Districts will head into this year's Men's Premier Division finals full of belief after upsetting two-time reigning premiers Figtree on Saturday.
In a see-sawing battle, it was Ethan White who proved the hero, bobbing up with 20 seconds left in the game to boot a crucial goal and seal a 11.8 (74) to 10.10 (70) victory.
While Saturday's win won't see them rise up from third on the ladder, it was the perfect tonic for Tigers co-coaches Glenn Haase and Mick Montague ahead of the finals starting next weekend.
"We've been talking all year about belief," Montague told the Mercury.
"The Tigers haven't really been in finals contention for so long, and we've got really close to Figtree and the Dogs but never won. So it's a confidence boost heading into finals."
Wollongong Bulldogs 19.11 (125) def. Shellharbour Suns 3.7 (25)
Wollongong Lions 17.24 (126) def. Kiama Power 3.0 (18).
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