Jockey Marlon St. Julien, 46, was involved in a serious spill on Saturday at Prairie Meadows, reports drf.com. In the ninth race, his mount Carbaugh was interfered with at the start and St. Julien went down hard.

“He went headfirst into the ground,” said his agent, Bobby Dean.

On Sunday, St. Julien underwent spinal surgery to fuse the C5 and C7 vertebrae, in an attempt to keep the pressure of his discs off his spinal cord. The rider was on a ventilator on Sunday, and his range of motion is under evaluation.

The rider of 2,468 winners with earnings just shy of $47 million, St. Julien has won multiple graded stakes races over the course of his career.

Read more at drf.com.