Mariota (elbow) is listed as active for Sunday's game against the Jaguars and expected to serve as the Titans' backup quarterback behind Blaine Gabbert, per Adam Schefter of ESPN.
Mariota has been making progress in practice since suffering an elbow issue Week 1, but the Titans are evidently inclined to take it slow with the QB, thus prompting the team to lean on Gabbert for the second straight week.