Bacchus Marsh will contest its first Ballarat Football League grand final since 1999.
The Cobras earned the direct path with a 48-point victory over Sunbury in the second semi-final at the Eastern Oval on Saturday.
Final scores: 21.12 (138) to 14.6 (90)
Jarrah Maksymow kicked seven goals and Damian Cupido five to send success-starved Bacchus Marsh supporters into raptures.
Bacchus Marsh blew its second finals appearance since 2001 - the qualifying final a week earlier broke the drought - with a sensational opening to the game.
The Cobras had four goals on the board in the first 11 minutes before Sunbury scored and when they kicked their seventh goal straight on 20 minutes they led by 41 points.
Sunbury finally got its act together to get four late goals to be within a manageable 21 points at quarter time.
Although the Lions were never completely out of it, only once did they look a major chance of closing the gap completely.
Sunbury moved within 13 points 11 minutes into the third term after a four-goal turn around, but that was to be as close as it was to get.
It was ultimately a left-foot snap from ruckman Daniel Burton from close to 50m out at the 16-minute mark of the last quarter which put the match out of reach.
That opened up a 30-point lead for the Cobras to ensure that even late goals from Sunbury did not seriously threaten.
Sunbury now awaits to play the winner of Sunday's first semi-final between Lake Wendouree and Redan in the preliminary final at the Eastern Oval next Saturday, while Bacchus Marsh gets a week off.
