The starting point guard for the No. 8 ranked Cardinals is the latest member of Rick Pitino's squad to go down with injury early this season.
Siva, Louisville's top playmaker, could miss Saturday's game at Butler with a sprained ankle, Pitino confirmed Wednesday.
"Peyton Siva stepped on Elijah Justice's foot and turned his ankle pretty bad," Pitino said. "He's day to day. I would say in most cases he probably wouldn't play (Saturday against Butler). I would say he's extremely doubtful."
Before spraining his ankle, Siva missed a week of practice with a concussion.
"Peyton Siva the other night was not the Peyton Siva as before (the injury)," said Pitino. "He's falling down on the ground doing all bad things because he missed eight days of practice. When you miss eight days of practice due to a concussion it's going to take you eight days to come back."
Buckles recently resumed individual instruction, but hasn't practiced with the team since practice began Oct. 14. Buckles, a 6'8 forward, is expected to return to action mid-December.
Blackshear tore his labrum in practice and had surgery on November 1. He could return this season, but won't be able to begin rehabilitation until mid-December, at the earliest.
Marra is out for the season after tearing the anterior cruciate ligament in his left knee against Lamar.
Stephan Van Treese, who recently resumed practice after missing the first month of practice with a knee injury, is expected to return soon, Pitino said.