CBS Sports' Bruce Feldman first reported last week that Wilcox would join Sarkisian and would announce the move from Washington following the Huskies bowl game on Dec. 27. However, in the time that report was filed and the Huskies' bowl game ended, Oregon announced defensive coordinator Nick Allioti would be retiring following the Ducks' bowl game.
There were unconfirmed reports circulating that the Ducks could be after Wilcox, a former player at Oregon.
Wilcox will replace Clancy Pendergast, who was not retained by Sarkisian, as defensive coordinator on the Trojans' staff.
Tuiasosopo will reportedly join USC's staff as a tight ends coach. A source says he was offered the same position on Washington's staff by new coach Chris Petersen.
Tuiasosopo is a graduate of Washington and quarterbacked the Huskies to the 2000 Rose Bowl Championship. He played in the NFL from 1997-2008 before becoming the assistant strength coach at Washington. He then moved to UCLA, where he was a graduate assistant and then tight ends coach the following season.
Tuiasosopo returned to Seattle with the Huskies in 2013 as the quarterbacks coach under Sarkisian.
Tuiasosopo was named the Huskies' interim coach after Sarkisian left on Dec. 2 for USC. Tuiasosopo is now 1-0 as a head coach since Washington beat BYU in the Kraft Fight Hunger Bowl.