Matt Cassel will start for the Tennessee Titans on Sunday as quarterback Marcus Mariota is inactive due to a hamstring injury, the team announced. ESPN's Adam Schefter first reported Mariota was not expected to play. NFL Network's Ian Rapoport, citing a source, reported "Mariota's recovery time from the time of the injury was 2-4 weeks." Mariota hasn't missed many games in two-plus-year career (five), but he has already had to deal with a few injuries. A broken fibula led to an early end to his 2016, while the hamstring issue is one of the first real nagging soft-tissue injuries he's nursed. When healthy, the 23-year-old has proved to be one of the top young quarterbacks in the NFL. He is an accurate passer and athletic runner who can pick up large chunks of yards in a variety of ways.