The shortening favourite off a plunge snapped up the prized $1million feature race (1600m) at Flemington by two-and-a-quarter lengths from the former Darren Weir-trained stablemate pair of Hawkshot and Amphitrite.

The first Group 1 winner for trainer Adam Trinder was also the first on the mainland for any Tasmanian-trained galloper in 133 years.

The last was Malua in the 1884 Newmarket Handicap and Melbourne Cup, which happened to be prior to the group racing system was first introduced more than four decades ago.

Trinder was gobsmacked after the race for the horse that cost just $11,000.

"We thought she was a lovely cheap little filly who would go out and do a job for us, but we never thought in our wildest dreams that that job would be a group one," Trinder said.

"This was my fiancee Leah's [Goodrick] filly at the sales - she loved her, so it's terribly satisfying."

The daughter of the stallion Needs Further, who is based at Armidale Stud near Launceston, Mystic Journey has proven to be a real find for one of Tasmania's most famous racing dynasties.

Grandfather Ray Trinder - ironically - could have broken the drought years earlier.

He first owned the 1972 Melbourne Cup winner Piping Lane, who won in an upset but handed the horse over to legendary Victorian trainer George Hanlon first.

The victory on Saturday has also ensured that Mystic Journey an entry into the world's richest mile race in the $5 million All-Star Mile in a fortnight's time.

"I now think she's on an upward spiral - I really do," Trinder said. 

"She's a filly that, every time we see her, she races better than the last time, so I think we are a long way from getting to the bottom of her.

"If she did go to the All-Star Mile, we would probably come back for the spring. 

"We would like to challenge her and have a look at a Cox Plate over a mile and a quarter."

Winning jockey Anthony Darmanin had some choice words for Mystic Journey.

"She's the Winx of Tasmania," he said.

But his jubilation was soured when he paid the price for his over exuberance on the ride of the Group 1 race after stewards suspended and fined him for illegal use of the whip.

Chief steward Robert Cram issued Darmanin an eight-day suspension for overuse of the whip, confirming the rider had hit his mount Mystic Journey 13 times prior the final 100 metres, which is eight times more than permitted.

He said Darmanin also hit the filly with consecutive strikes twice in the drive to the line before fining him $500 for the act.

Darmanin's holds several sanctions in Tasmania and Cram said that the Guineas, being a Group 1, the suspension and fine were appropriate penalties.

Darmanin is likely to return to Flemington in two weeks to partner Mystic Journey in The All-Star Mile if she is announced as a wildcard.

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