Vulcan received a horror run when trapped three wide in his heat at Shepparton last Saturday, forcing Butt to take the unusual move of pulling right back to last.
He experienced traffic problems afterwards and could only finish sixth and with most of the first night major points scorers expected to be prominent again this week, Vulcan needs to win or finish second to be guaranteed a spot in next Saturday's A$250,000 final at Melton.
Butt is confident that will happen.
"While we got a terrible run last week he actually went a lot better than he did when he was beaten at Omakau the start before," said Butt.
"So I am happy with him. I think he just needs no bad luck this week and with the smaller field we can achieve that.
"And I look at it like this. We are in a weaker heat and if we can't run first or second there then we probably can't win the final anyway."
Like bookmakers on both sides of the Tasman Butt rates the New Zealand trotters as the ones to beat in the series.
"I think they showed that pretty clearly the other night as they all went well."
Kiwi trotters completely dominate the Interdom market, although one of those favourites, Springbank Richard, has a change of driver.
Trainer Phil Williamson steps in to replace son Nathan, who has commitments at Invercargill's big meeting on Saturday.
But the trotters won't even be the stars of the show on Saturday.
Not only does New Zealand pacing hero Auckland Reactor return in the $20,000 Pure Steel, on trial for the Hunter Cup on Saturday week, but the A$125,000 Ballarat Cup is one of the races of the season.
It pits champion veteran Smoken Up (two on the second line) against the heir to his throne in Sushi Sushi (barrier seven), who is going for 17 wins on end.
Against them will be Kiwi stars The Gold Ace (13), Pembrook Benny (one) and Highview Tommy (four).
