USC starting defensive tackle Josh Fatu is currently in concussion protocol after being involved in a multicar accident, Trojans coach Clay Helton said Tuesday.
Fatu, who has 27 tackles and seven tackles for loss this season, will continue to be evaluated; Helton classified his status as "day-to-day."
Helton said the accident was not Fatu's fault.
If Fatu is unable to play on Saturday against Notre Dame, Brandon Pili would be expected to start in his place.
Helton also announced that another of Fatu's backups, redshirt senior Kenny Bigelow, will transition into a role with the program as a result of recurring knee injuries. Bigelow arrived at USC ranked as the No. 21 player in the ESPN 300 in the Class of 2013, but his career has been mired by injury problems. Helton said Bigelow hopes to one day become a coach and that his new role will help prepare him for that.