Wangaratta booked a date with arch rivals Myrtleford in the senior men's cup final after edging out Boomers 3-2 in the semi-final at Willow Park on Sunday.
Thomas Romero's strike in the second half was the decisive blow in an entertaining contest.
Despite the loss of coach Andrew Grove, who ruled himself out with a quad injury on Saturday, Boomers dominated the first 30 minutes and should have had more than a 1-0 lead.
Pieter Noordewier put them ahead in the 21st minute with a classy finish, but they gifted it back 15 minutes later when Mason Nhansana was brought down in the box and Andrew Barisic stepped up to convert the penalty.
Wangaratta took the lead six minutes later when the Boomers' defence failed to clear a cross from Adam Burchell, leaving centre back Nikola Bukvic with the simplest of finishes at the near post.
But Boomers hit back in the final minute before the break thanks to a brilliant run and finish from young gun Kye Halloway to leave it locked at 2-2 at the break.
Wangaratta began to get back on top in the second half and took a 3-2 lead on the hour mark when Romero hit the back of the net.
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The introduction of Josh Masters in the middle of the park was key for the Devils as they limited Boomers' opportunities for the final 30 minutes.
Matt Mildren kept Boomers in it with a brilliant one-on-one save against Adam Burchell, but Wangaratta held its nerve to reach the final for the first time since they won it in 2015.
"That was intense. I reckon that game took a couple of years off my life," Wangaratta coach Daniel Vasilevski said.
"They were quality today, they came out firing and we just weren't ready for it."
Vasilevski had planned for Grove to play, but knew they were still going to be dangerous without him.
"We were just trying to ride the wave of pressure and we got the release from the penalty and we started attacking a bit more," he said.
"We knew come 60-70 minutes we were going to start running over teams and the game would open up because we're a very fit side, and that's what happened. It was such a satisfying win."
Grove felt his side played well enough to win despite missing him in attack and Dylan Nhansana in defence.
"We were by far the better team in the first half and really should have went at least 2-1 up, which would have given us a decent chance to hold it," Grove said.
"They took control of the game in the second half. We lost the middle of the park.
"I thought we really controlled that well in the first half, but once we lost the middle we couldn't play Pieter, 'Honda' (Shunsuke Kadano) and Kye up front because they weren't getting the service like they were in the first half.
"We gave them a red-hot go like we did all season, but we just weren't quite good enough."
Burchell suffered a gash to his knee, but played the game out, while Riley Hamilton (groin) and Brendan Barton (illness) won't be in any doubt for the final.