Apprentice Patrick Moloney will have surgery on a broken left ankle after a fall at Flemington on Saturday.

He might also require surgery on his right ankle, which was also fractured, according to Victorian Jockeys' Association chief executive Des O'Keeffe.

Moloney fell from Sweet Starlett when near the tail of the field approaching the home turn of the Prudential Plate.

"His left ankle requires surgery. That's having a plate put in it tomorrow morning," O'Keeffe said.

"The right ankle is fractured, but not as severely as the left. So they will decide whether to operate on it at the same time.

"They may decide it (the right ankle) could heal quicker in a moon boot."

The ankle injuries to Moloney are a massive blow to his hopes of winning the Melbourne apprentices' premiership.

Moloney has a five-win lead over Katelyn Mallyon with under four months of the season remaining.

Stewards determined Moloney clipped the heels of Soosa Rama in front of him.

"He (Moloney) was coming back to get some cover and just got too close to heels," chief steward Terry Bailey said.