Carol Heffernan reasons if it's good enough for Mick Kent, it's good enough for her.

In an unorthodox move for Rich Jack, Heffernan will follow a lead from her in-form Cranbourne neighbour when the speedster runs in the Brett and Mark Wilson Sprint at Caulfield on Saturday.

Rich Jack ran a first-up fifth behind Supido over 1200m at Flemington on Anzac Day and Heffernan has been having trouble finding a suitable race.

After watching Kent bring Supido back 200m in distance to win at Flemington last week, Heffernan thought Rich Jack was up to a similar task.

"There was nothing else for him unless I took him up to 1400 (metres)," Heffernan said.

"I just doubt if he would get that distance so we thought we would come back to the 1100 and hopefully in three weeks time there's a 1200-metre race somewhere.

"It made me feel a little better when Mick Kent did it with his good horse."

Heffernan was pleased with Rich Jack's first-up run when he led before tiring to be beaten 3-1/2 lengths.

She said it took the gelding a few days to get over the run.

"He's benefitted a lot from that first-up run as he had a really big blow after it," she said.

"He came home and ate up but it was his mannerisms, they were a bit quieter than normal.

"We just took him on nice long walks and a bit of work around the paddocks at home and he's bounced back well and his trackwork has been good."

Darren Gauci, a two-time winner aboard Rich Jack, takes the ride on Saturday.

Rich Jack has firmed from $10 to $7.50 to hold down the second line of betting behind Belesron at $4.80.