The Titans announced the moves Wednesday.
Whitehurst had the best season of his career last year starting five games for Tennessee and throwing for 1,326 yards with seven touchdowns and only two interceptions. Coach Ken Whisenhunt helped bring Whitehurst to Tennessee to help teach Jake Locker, then Marcus Mariota his offense. But the Titans fired Whisenhunt last week.
Cobb, Tennessee's fifth-round draft pick out of Minnesota, could make his NFL debut Sunday against Carolina after landing on injured reserve with a calf he hurt Aug. 27.
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