"Man I loved it at Washington," O'Brien said. "They offered me on Saturday as a linebacker and I'm totally fine with that. I love the linebacker coach, Coach Sirmon and also like the DC Justin Wilcox a lot. I spent a lot of time with coach Sirmon and he's an awesome guy and I'm excited to play for him.
"I know he was a great player in college and I can't wait to be coached by him and learn as much as I can. They're planning to run a multiple look defense with some 3-4 and 4-3 formations. I'll play the Sam ‘backer (strong side linebacker) in both and I don't think I'll have any problem gaining the weight to make that move."
O'Brien said the decision of his friend and teammate, Dane Crane, to commit didn't play much of a role in his decision.
"It's awesome to play with Dane but I made this decision on my own and so did he," O'Brien said. "It was cool, we got together Saturday night and asked each other, ‘what do you think about this place.' Dane said he wanted to commit and I said I was ready too. My mom came up with me and she loved the place but wanted me to come home and sleep on the decision before making it official.
"I also considered Oregon and I have a lot of ties to Colorado and I loved it there too but Washington was the best fit for me. Like I said, I really loved it there and the chemistry between the players and coaches is awesome. Coach Sark said he wants to try and make it like a high school atmosphere where everyone is on the same page and playing for each other and I love that. I'm very comfortable with this decision and thrilled to be a Dawg.