Zayas, who took last year's summer riding title at Gulfstream and fall title at Gulfstream Park West, was unseated during the running of Friday's ninth race. Zayas, tied for the lead in victories at the current meet with Juan Leyva, Jose Caraballo and Eddie Castro, missed five weeks during the spring meet with a fractured right hand.
"He's out for four-to-six weeks, but he doesn't need surgery," Fuentes said.
Jonathan Gonzales, who was also involved in the spill with Zayas, took off his mounts Saturday due to soreness.
Jockey Harry Hernandez, who fractured his nose Friday when he was unseated at the start of the seventh race, was cleared to ride Saturday.