Trainer Mick Price has maintained his average with a winner on each day of the Melbourne Cup carnival.

The jewel in the crown was Saturday's Victoria Derby win by Tarzino but Price was also pretty happy to win a three-year-old sprint with Invincible Heart on Cup day.

He continued the run with Secret Agenda in Thursday's Group Three Gucci Stakes (1100m), run on a soft track just before rain and hail hit Flemington.

The sprint field split into two divisions with Secret Agenda, the $4 favourite, a clear leader on the inside.

She had 2-3/4 lengths on Tempt Me Not ($15) who raced on the grandstand side as did third-placed Lake Geneva ($9).

"I think she handled that track really well," Price said.

"She's Group Three placed on two occasions at her two tries, and for her to put one away makes her a really valuable broodmare."

Her jockey Damien Oliver said the filly was more than comfortable on the wet surface.

"We had a nice sit off the leader and she really loved the ground. She hadn't seen a soft track before but today she just flew through it."

After the race, the rain forced a delay in the program and a downgrade of the track to heavy.