Tuiasosopo was offered the opportunity to coach tight ends at both Washington and USC but said his familiarity with new Trojan coach Steve Sarkisian and the opportunity to learn at a new program were too much to pass up.
"I have a great relationship with Sark and have known him a long time," Tuiasosopo said. "He was my coach for three years when I was with the Raiders and I really enjoyed coaching with him this past season. I'm very familiar with the staff he's putting together since I worked with a lot of those guys here at Washington and I'm excited to see what we can do at USC.
"It was a very tough decision for me, tougher than most since I played at Washington and I'll always be a Husky but I had to take the emotion out of the decision. I had to look at what was the best opportunity, not just short term but long term as well.
"USC is a legendary program with great tradition and I'm excited for the opportunity to learn and progress as a coach. It's always hard to leave home but I'm a coach, this is the profession I chose for myself. As a coach, you have to make tough choices but I felt like this was the best opportunity for me and one I couldn't pass up."
Along with coaching tight ends, Tuiasosopo will also have the title of assistant head coach. His goals are to one day be a head coach and that was another reason for the move.
"Professionally, you want to keep moving forward, you don't ever want to stand still, in one spot," Tuiasosopo said. "I want to be a coordinator one day and then a head coach. I wanted to learn at a new program and continue to see how things work at a new University.
"USC has such great history and tradition and I'm looking forward to seeing how they do things there. I know it's home for Sark and he's very excited to build the program back up. I know Tee Martin really well, we were with the Raiders together and I know all the other coaches that I was with at UW and it's a great staff.
"Now leaving Washington doesn't take away my love for the school. I love the school and the fans and wish them the best. I don't know Coach Petersen but he has a great track record and I'm sure he'll do great things. I'm excited to leave our own mark at USC and establish something big here. USC has high standards of winning and being the best of the best. That was big for me as a player and I can't wait to get started."
Tuiasosopo just flew in to Los Angles on Monday and hasn't stepped on campus at USC yet.
"My wife and I came down and right now, we're just looking for a place to live," Tuiasosopo said. "The great thing is I was just here a year ago at UCLA so I'm very comfortable with the area and know my way around here pretty good already. We haven't met up as a staff yet but from a recruiting standpoint, I've recruited all over Southern California and in to San Diego so I'm willing to do whatever they need me to do.
I'm excited to coach these tight ends as well and I'm comfortable with that position. It's what I coached at UCLA so I know I'll need to brush up some things but I'll be ready. I'm excited to be part of this staff and can't wait to see what we can do."