The news came as a shock to Laurinaitis, the team's all-time leader with 653 solo tackles, as he told Jim Thomas of the St. Louis Post-Dispatch.
"I didn't see this one coming," he said.
Laurinaitis also noted that the team asked him to make himself available to the media in Los Angeles to help build up the team's move.
"So I was like, if they're gonna call and ask me to do that, I must be all right," he said. "I thought maybe at worst, a pay cut. I still felt like I was producing."
The 29-year-old signed a five-year contract extension in 2012 worth $41.5 million.
He was drafted in the second round by the Rams in 2009 and has appeared in all 112 games over the past seven seasons. He's also had three seasons with over 100 solo tackles and four years with at least three sacks.
With Laurinaitis' athleticism and his intensity, he became an integral part of the Rams defense:
Los Angeles Rams @RamsNFL
#Respect ✊ @JLaurinaitis55 https://t.co/cpyO5dooGn9/29/2015, 3:20:15 AM
Those intangibles reportedly made it a difficult cut for head coach Jeff Fisher.
"He said it was one of the toughest (cuts) he's had to do in his career," Laurinaitis said. "Up there with (Steve) McNair and (Eddie) George."
However, he has seen a drop in production, going from 85 solo tackles in 2013 to just 60 in 2015.
According to Thomas, the younger Alec Ogletree, 24, is expected to step in and take Laurinaitis' place at middle linebacker as the longtime Ram now searches for a new home.
"That makes sense," Laurinaitis said. "Alec will do a good job there. It's a new chapter now. It's the first time in my career I get to look around and see where I want to go."
Laurinaitis appears to have some productive football left in the tank despite his decrease in production, especially given his ability to stay on the field. For teams looking to bring a steady veteran presence to their linebackers unit, Laurinaitis would be a welcomed addition.
Stats courtesy of Pro-Football-Reference.com.