After eliminating 2014 champions Central West with a 14-3 win in Saturday's semi-final, the Illawarriors accounted for traditional rivals Newcastle 24-14 in the final.

Illawarra last held the Caldwell Cup in 2004.

Illawarra led 6-0 after a pair of penalty goals before Newcastle forged ahead 7-6 with a converted try. The Warriors responded and took a 14-7 lead into half-time.

The score swelled to 24-7 before the Novocastrians cut the deficit to 10 with 10 minutes remaining.

But the Illawarriors would not be denied - the perfect parting gift for long-serving captain Gavin Holder.

Illawarra number eight Paul Tuala captured Player of the Game honours. Coach Shaun McCreedy said the Warriors gained a "quiet confidence" after the hard-fought victory over Central West on a rain-soaked ground.

"Their focus was on today. That was the big one. "We knew we couldn't play with a lot of width because of the wet, muddy conditions, but we executed with ball in hand and played down the right end of the park and applied pressure."

McCreedy said seeing the Warriors crowned Country champions was on a par with guiding University to last year's Illawarra Rugby premiership.

"I'd be lying if I said it wasn't," he said.

"Coaching at this level ... you've only got a short amount of time to mould them into a unit and get them to believe in each other and in the system that you put in front of them.

"The satisfying part for me was knowing they'd done everything they could when they walked off that field, and in doing that they got the result."