It's a big decision for the franchise. Locker was the No. 8 overall pick in the 2011 draft, but he's struggled to stay healthy as a pro. His play on the field has been up and down, with flashes of real promise.
The Titans gave Mettenberger additional first-team reps at practice Wednesday, where Locker was not made available to the media for the first time all year, according to Jim Wyatt of The Tennessean. Whitehurst said he was not allowed to talk to reporters.
The team wants to see how good Mettenberger is in order to know whether to draft a quarterback in the first round next year. The Titans believe they'll get more big plays with Mettenberger, and live with the mistakes.
In short: It's Mettenberger's job to lose now.