"We are evaluating. Marcus is going to do everything he can to get ready, like every player is going to do," Vrabel said after Friday's practice. "I would anticipate both of those guys playing at some point and time."
Mariota injured his right elbow as he was carrying out a run fake during a read-option play against the Miami Dolphins in the season opener. He said he lost feeling in his hand but went back in the next series, only to be removed later in the game after throwing his second interception.
Mariota was listed as a full participant Wednesday but was limited in practice Thursday and Friday. Mariota didn't throw any passes during the individual portion of practice over the past two days. His throws tended to wobble a bit during the open part of practice to start the week.
Vrabel didn't offer a glowing perspective about Mariota's progress.
"I would say it is status quo," he said. "I think it's about stagnant as far as his improvement. It kind of is what it is."
Starting left tackle Taylor Lewan, who went through the concussion protocol, will not play Sunday when the Titans host their AFC South division rivals. Lewan was hit by Dolphins defensive end Andre Branch as safety Reshad Jones returned an intercepted pass intended for wideout Tajae Sharpe.
Lewan was sent home from the Titans facility on Wednesday and told to get rest, then was not in the building on Thursday.
The Titans got some good news Friday as Vrabel said two top rookies, inside linebacker Rashaan Evans (No. 22 overall draft pick) and outside linebacker Harold Landry (No. 41), are expected to make their NFL debuts.
Evans missed most of training camp with a hamstring injury but was a full participant in practice for the first time Wednesday.
Landry got off to a strong start during preseason -- he posted a sack against the Green Bay Packers -- and is expected to provide extra juice off the edge. An ankle injury that occurred during punt coverage against the Pittsburgh Steelers limited Landry in practice leading up to the season opener.
After not practicing Wednesday, Landry was a full participant Thursday and Friday.