The lightning-fast Johnson was one of the league's most dynamic and explosive playmakers early in his career. He ran for 2,006 yards in 2009 and is one of only six players to run for at least 1,000 yards in his first six seasons, along with Barry Sanders, Curtis Martin, LaDainian Tomlinson, Eric Dickerson and Corey Dillon.
But Johnson averaged a career-worst 3.9 yards a carry and didn't have a run longer than 30 yards in 2013. He was scheduled to make $8 million in 2014.
The Titans found the combination of sinking production and high cost to be unpalatable and are expected to draft a running back to work with Shonn Greene and free-agent addition Dexter McCluster out of the backfield.
Johnson was the 24th selection in the 2008 draft out of East Carolina.
After three seasons when he ranked as one of the league's best values, he sold himself as a "playmaker" who shouldn't be constrained by the values placed on running backs, and after a training camp holdout in 2011, he got a four-year, $54 million contract. He's made $31 million over the last three years.
The Titans will save $4 million with the move and will carry $4 million in dead money.
Information from ESPN.com's Paul Kuharsky was used in this report.