The future of Boom Time as a racehorse will be decided by his performance at Caulfield, the scene of his biggest win.

The Lindsay Park-trained 2017 Caulfield Cup winner, owned by senior trainer David Hayes, has flopped in three runs since a tendon injury put an end to his spring campaign last year.

Saturday's Catanach's Jewellers Handicap (2000m) will be the last opportunity Boom Time has to show he is still a racehorse, or whether it is time for retirement.

Lindsay Park had been trying to replicate the off-season success Boom Time had last year when he ran second over 1800m at Flemington before scoring over 2000m at that track last May.

"He's at his distance, he's had three runs, if he doesn't win, or go close, he'll probably be retired, but if he runs well he'll campaign in the spring," Hayes said.

"His trackwork suggests he's on song but his race performances have been very poor."

Boom Time led over 2000m at Flemington on May 18 but was beaten soon after straightening, finishing last, more than 18 lengths from winner Mantastic.

Lachie King, who rode Boom Time to his most recent victory, replaces fellow apprentice Lewis German on Saturday.

Hayes said the stable could not find anything amiss with Boom Time and he has been over a few hurdles during the week in a bid to rekindle his interest.

"He's a stallion and that's why a lot of seven and eight-year-old stallions aren't racing," Hayes said.

"He might be looking for greener pastures and that will be decided on the weekend."