Fiorente mare lands big payday after barrow win in Country Final.

Picaroon scored an unlikely win for Warrnambool in the rich Melbourne Cup Carnival Country Final at Flemington on Thursday.

The six-year-old daughter of Fiorente is only in work after failing to get in-foal and she lasted in a driving go to score a narrow win in the $500,000 event.

It was the richest win for trainer Tom Dabernig since leaving Lindsay Park and going out on his own and he thanked both Picaroon's owner Dr Richard White and former trainer Michael O'Leary for their efforts.

"Richard sent her to stud to get her in-foal (but she missed) and that is how she ended up with me," Dabernig said.

"I must thank Michael O'Leary. She came to me in great order, we've just guided her along the way and she's done all the hard work."

The Melbourne Cup Carnival Country Series consists of $100,000 heats run at Country Cup meetings throughout the Spring Carnival and is for trainers who did not have more than 15 winners last season.

Picaroon finished fourth in the heat run at Murtoa on October 7 before winning the event run at Hamilton seven days later.

The $8 chance relished a sweet ride from Melbourne's premier rider Blake Shinn, who himself as country origins, being brought up in Kilmore, and had to work hard to reel in leader Soaring Eagle before then having to stave off a late charge from $4.40 equal favourite Euphoric.

At the line Picaroon had a long-head to spare over Euphoric, who finished a head clear of Lady Jones($8).

"This race is for the country trainers and it's worth great money and Tom Dabernig is a great bloke, has prepped this horse really well and targeted the race," Shinn said.

"They're not easy to win these big ones because a lot of them are targeted to this race but fortunately we got the luck on the day."

With the Melbourne Cup Carnival Country Final winner's cheque secured, Dabernig said the objective could now be to try and secure some Black Type for Picaroon before another crack at motherhood.

"It's not the end of the carnival now that they've extended it, there's a Group Three mares' race over a mile at Sandown, and that'd be good to get a little bit of black type," Dabernig said.