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.
The Wombats head into the grand-final qualifier with renewed vigour, after hammering Bowral 81-7 on Saturday.
It was an important hit-out for Joe Aiona's chargers, whose lead-in to the finals has been far from ideal considering the Wombats have only played some three games in eight weeks.
Campbelltown finished fourth despite losing to Shoalhaven. As a result the Harlequins will meet Kiama in an elimination final at Ocean Park next Sunday.
The Kiama Cows head into the clash in fine form following a comfortable 52-24 win over Tech Waratahs at Kiama Showground.
The Cows never looked like losing after racing to a 21-0 lead early on before settling for a 28-7 halftime lead.
Kiama were just as ruthless in the second half and raced out to 52-12 advantage before the visitors scored two late tries.
There was some joy for Tech-Tahs, with retiring skipper Bryn Edwards kicking a goal just before full-time.
Nico Cowley and Frank Podger bagged two tries each for Kiama, with Robert Siteine, Paul Asquith, Ian Baker and James Asquith also crossing for five-pointers.
Skipper James Asquith, who finished with 17 points thanks to a try and six goals, said the team was happy with its form heading into its elimination final against Campbelltown.
'There's always stuff to work on but I thought that was one of our best 80-minute performances," he said.
"It was good to play Tech Tahs, they're similar to Avondale and Campbelltown as they have a lot of big bodies and ball carriers.
"We just focused on playing the type of rugby that we may want to replicate next week.
"It was a good performance. We will worry about Campbelltown during the week."
Kiama coach James Patrick was also satisfied with his team's showing against the Tahs.
"I thought we were good for 70 of the 80 minutes," Patrick said.
"It was good to play well and fine tune ahead of next week's finals.
"It's an exciting time for Kiama, we're playing in the semifinals for the first time in 10 years."
Meantime, in the other fixture on Saturday, Shamrocks beat University 25-5.
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