Despite trailing 19-7 at halftime, Shamrocks produced a dominant second half performance to finish over the top of the defending premiers and secure a 39-22 victory.

Shamrocks coach Paul Ridgway said his side was determined to earn the opportunity to take on Avondale at WIN Stadium next Saturday.

"We've worked really hard for this," Ridgway said. "We've earned ourselves an opportunity to meet Avondale in the grand final.

"The boys really wanted it, they showed that in the way they played, they controlled the ball for long periods of time, worked out of trouble in the first half and worked really hard to get the win.

"It feels fantastic at the moment, but we've got to get our nose to the grind stone now. Avondale's a massive challenge for us."

With a strong wind behind their backs in the opening 40 minutes, it was Bowral who started the game on top.

The dominance could only be converted into a 12-point lead at the break, with Shamrocks defending fiercely to remain in the game.

Despite running into the wind in the second half, Bowral were straight back on the attack after halftime.

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The match turned in an instant, however, with Shamrocks turning a Bowral turnover into a 95-metre break before Vuik crossed for the first of his three tries.

Vuik was in again just minutes later and suddenly it was Bowral who were reeling.

Slowly, Shamrocks ground their opponents down, five-eighth Thomas McDevitt ensuring the game was played in Bowral's half.

With the wind forcing Bowral to run the ball out of their own end, Shamrocks were able to turn their territorial dominance into points.

Given the strength of the wind, Ridgway was confident Shamrocks would finish over the top of Bowral in the second half.

"I wasn't overly concerned at halftime. When you're behind at any game, you're concerned, but the wind was so strong and their kicks had pinned us in the corner, trying to get out, we couldn't kick it and had to burn so much energy.

"We knew if we could control the ball for long periods of time with the wind behind us, we could do what we needed to do."

While the matched turned on Vuik's first try, it was a 10-minute period midway through the second half that acted as the defining phase of the game.

With Shamrocks centre Dale Sullivan sent to the sin bin, Bowral had numerous opportunities to hit back.

Woonona held firm, however, with the Blacks able to score just three points during the 10 minutes they were playing against 14 men.

"That period was really crucial," Ridgway said. "We moved Daniel Porra, who was fantastic for us, out of our backrow and into 12, just to shore that up.

"We played one down in the forward pack and that got us through. Anytime you're playing with 14 players, it's difficult, so it was a good result not to concede any tries."

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