Bowral's big-hearted Small Blacks will be thrust into the land of the giants on Sunday when they meet the monstrous Vikings in the under-13s grand final in Wollongong.

The brilliant young side booked a spot in the decider with a gutsy 17-5 win over the Shamrocks in Bowral at the weekend.

In a superb display of running rugby, the young Blacks used their blistering pace and mobile pack to run in three tries to one and give them a shot at going one better than their first grade senior clubmates.

13s coach Laurie Gordon will direct his team to throw the ball around against the Vikings in a bid to nullify the oppositions menacing forward pack.

"They're twice our size and the size of men," he said.

"We might have a smaller pack but they're very fast and skillful and our backline is the best in the Illawarra.

"It's going to be a tough game and we need to concentrate on playing it wide."

Best players for Bowral in Sunday's final were Tyler Jones, Sam Burnham, Duncan Shrimpton, Ben Lewis, Charlie Webb and Jesse Streeter.

The side finished the regular season with an 11-3 win-loss record and the 27 player squad boasts ten current Illawarra reps as well as four PSSA state stars.

Most of the talented side are also products of the Bowral Blacks mini system.