Early in the second half, Maheno’s Robbie Smith turned down a penalty from in front and just 20m out, instead going for a try which never eventuated.
Earlier, Valley centre Mathew Vocea had taken a quick tap from an easily kickable penalty just beside the posts and scored to help his side trail by just five points at halftime.
It was that sort of final with things on a knife edge but Valley was more composed and ran out the winner 22-19 at a mostly empty Whitestone Contracting Stadium on Saturday.
Brothers-in-law, halfback Smith and second five-eighth Nick McLennan, combined for McLennan to score and, midway through the half, Maheno No8 Marcus Balchin crossed from a lineout.
Valley co-coach Shane Carter had impressed upon his players the need to set the pace of the game and keep the ball away from Maheno.
"If we kept up the pace we would have the edge as my boys were very fit and when we turned around with the wind at out backs trailing by just five points we knew we had a real chance, but we knew we had to shut down Maheno’s attacking skills in the backline.” he said.
The plan worked well as Maheno turned around with a five-point lead at 19-14.
Midway through the first half, flanker and captain Cameron Rowland breached the defence and Valley fullback Taine Stirling outpaced the cover defence to score. Ben Paton converted.
But Rowland lifted his side breaking down the left flank before the movement broke down when Maheno infringed. Vocea then made the instant decision and achieved the reward.
Carter believed the third quarter was the key.
"We knew we had to apply a lot of pressure emphasising our line speed pushing up on them, creating pressure on them without actually having to tackle them.
"I think it really showed up in the final 10 minutes as we defended our line.
Paton added a penalty and midfielder Hayden Gold and Stirling showed their ability late in the game.
Hooker Sam Sturgess had a big game for Valley while the backs worked hard.
Maheno tried hard all game but could not break through a good defensive effort from Valley.
- Terry O'Neill