It's either boom or bust for the connections of sprinter Rocket Tommy.

From 26 starts, Rocket Tommy has won on nine occasions but has failed to fill a place in his other 17 appearances.

A Swan Hill win at his most recent start on June 9 came a year to the day after victory at Flemington, his third win over the straight course.

Now he is back in form, trainer Gwenda Johnstone and her husband Mick are hopeful he can string back-to-back successes together in Saturday's Stable Staff Recognition Handicap (1000m) at Flemington.

Mick Johnstone knows Rocket Tommy as well as anyone and says the sprinter is a quirky horse who either wins or finishes out of the money.

"He's frustrating in that sense," Johnstone said.

"You'd love him to run a place, sometimes it's like winning a race.

"At Swan Hill he sat third on a hot speed and he worked to the line well, and importantly kept in front."

Johnstone said despite lumping 61.5kg to victory last time Rocket Tommy appreciated the class drop.

After his win at Flemington last year, Rocket Tommy rose to 92 in the ratings and found the class he was racing against too tough.

"I think the firm tracks and the company was a bit strong," Johnstone said.

"After he won at Flemington he got up in the ratings and the weight and class he had to race against was a bit beyond him.

"To go to Swan Hill and carry 61.5 (kg) and still beat them was a big effort."

Johnstone rides Rocket Tommy in his work and says he has not gone backwards since his Swan Hill victory.

"He's feeling good, working well, he's had a good space between his races," Johnstone said.

"He's fresh and ready to go.

"We'll tell Brad (Rawiller) to just ride him where he's comfortable."