Trainer Bryan Guy believes he might have found the key to former boom galloper Magic Cassius who returned to winning form at Ipswich on Wednesday.

Magic Cassius was rated a future Group standard horse when he won six of his first eight starts for Gosford trainer Angela Davies.

His form was so good he was installed a short-priced favourite for the 2012 Ramornie Handicap at Grafton but was scratched on race eve with a foot infection.

Magic Cassius has struggled to regain his best form since then and was transferred to the Gold Coast-based Guy in April.

The gelding finished near the tail of the field in his first two Queensland starts but Guy saw a glimpse of form from Magic Cassius in a recent barrier trial.

Magic Cassius ($11) responded to a smart ride from Jim Byrne to win the Benchmark 85 Hcp (1200m) on Wednesday.

"I think it has been a matter of him getting his confidence back. He was back up to 1200 metres today and his record at that distance is eight starts for six wins," Guy said.

"We aren't getting carried away with him and we will take him along slowly through the winter. There are plenty of races for him."

Guy notched a winning double when his two-year-old filly Grapevine ($2.20) survived a protest.

Grapevine is likely to press on to a two-year-old race on Ipswich Cup day, June 14.

Meanwhile, Guy said his handy mare Jacquetta would be retired after running last in the Benchmark 85.

Jacquetta, who won five races and was black type placed, will go to stud in the new breeding season.