The 2019 first-round pick, who is returning from a torn ACL, took the practice field for the first time Wednesday. The Titans play the Los Angeles Chargers on Sunday.
Coach Mike Vrabel said Friday that the Titans wanted to see how Simmons' knee responded after going through practices before making an official announcement.
"As the week went on, my technique got better," Simmons said after practice Friday. "I feel great. The good thing about it is I didn't have much swelling. I knew I had an injury, but I didn't go out there all timid. I went out there full force, and it felt great."
Simmons tore his ACL in early February and was placed on the non-football injury list before training camp. The injury caused Simmons, once a top-five draft prospect, to fall to the Titans at No. 19.
The Titans have released defensive tackle Matt Dickerson to make room for Simmons on the 53-man roster,. Tennessee also released defensive lineman Brent Urban and promoted outside linebacker Derrick Roberson from the practice squad.