Titans to start Zach Mettenberger for injured Marcus Mariota

— -- NASHVILLE, Tenn. -- Zach Mettenberger will get the starting nod Sunday for the Tennessee Titans against the Falcons as coach Ken Whisenhunt declared Marcus Mariota out after a third day of missed practice with a sprained left knee.

"He's frustrated because he wants to play," Whisenhunt said of Mariota on Friday. "We want to get him on the field as soon as possible. It just won't be this week."

Mariota was injured last week on a low hit by Miami's Olivier Vernon for which the defensive end was fined.

Now the Titans turn back to the big-armed Mettenberger, a 2014 sixth-round draft pick from LSU who started six games for them during a 2-14 season.

The Titans didn't win any of those six games, but he showed some NFL-caliber traits. His preseason play left many analysts suggesting teams with shaky quarterback situations should call the Titans with trade offers.

"I think there is a good confidence level in Zach," Whisenhunt said. "He had a really good preseason. He's been around the guys, there's a good energy in that room with the quarterbacks. It's a good feeling with those guys. So they all support each other, and we feel good.

"We're confident in Zach and he's worked really hard physically. You can see it. He moves around better, he's throwing it well."