The Boilermakers' top two offensive players were hurt on the same play on Saturday.
Coach Jeff Brohm says Purdue will face No. 12 Penn State without starting quarterback Elijah Sindelar or All-American receiver Rondale Moore.
Sindelar will have surgery for a broken left collarbone. Brohm did not provide a diagnosis Monday on Moore's left leg injury, though he hoped to have more information later this week.
Purdue's top two offensive players were hurt on the same play in Saturday's loss to Minnesota.
Sindelar hurt his left shoulder when he was driven into the ground on a sack. Moore was injured after being shoved by a Minnesota player, appearing to trip and then taking an awkward step before falling to the ground while running a route.
Purdue (1-3, 0-1 Big Ten) has lost two straight.