O'Regan agreed to terms on a one-year deal with KHL club Kunlun Red Star on Monday.
O'Regan was sent to AHL Grand Rapids on Wednesday.
O'Regan was recalled by the Red Wings under emergency conditions Tuesday.
Detroit acquired O'Regan from Anaheim in a three-team deal that sent Michael Del Zotto to the Ducks and Givani Smith to Florida.
Anaheim waived O'Regan on Sunday, per CapFriendly.
O'Regan was demoted to AHL San Diego on Wednesday, Elliott Teaford of The Orange County Register reports.
O'Regan was reassigned to AHL San Diego on Friday, per the AHL Transactions list.
O'Regan notched an assist and two blocked shots in Tuesday's 4-3 overtime loss to the Rangers.
O'Regan was elevated from AHL San Diego on Thursday, per Elliott Teaford of The Orange County Register.
O'Regan was reassigned to AHL San Diego from the taxi squad Wednesday.