Quarterbacks and rookies are scheduled to report to the Tennessee Titans’ training camp Monday and there is some symbolism in that for quarterback Marcus Mariota this season.

Mariota prepares to embark on his fifth and most pivotal NFL season determined to prove his credentials as a franchise quarterback all over again.

Mariota had a promising rookie year in 2015 and an even better sophomore campaign until suffering a broken leg against Jacksonville that ended his season in the 14th game and set him back for 2017.

Since then, questions about durability and consistency have hung over his career to the point that his future with the franchise now rides on how well he — and the Titans — perform this season.

The team invoked a fifth-year option on his contract for this season, a rarity for high quarterback draft selections (second overall in 2015) who usually get new, long term deals, to gauge whether there are grounds for a renewed and deeper investment.

If Mariota returns to form, the Titans will need to ante up on a longer deal or slap a franchise tag on him. Either way, he will likely make upward of $23.5 million for 2020 with the possibility, if his performance inspires, of his agents securing a mega-moolah multi-year deal. Mariota is represented by the same agent, Ryan Tollner, who engineered Carson Wentz’s four-year, $128 million extension with the Eagles last month.

If Mariota struggles, the Titans can turn their search for a centerpiece quarterback elsewhere (USA Today has projected Oregon’s Justin Herbert as a likely draft pick) and a far less bankable tour of free agency looms for Mariota.

Characteristically for Mariota, who subscribes to substance over talk, there has been little said and much sweat invested in this offseason. In a brief stopover between an active calendar of offseason workouts, sessions with his receivers and physical training, Mariota said, “To be quite honest, I’m not even thinking about (the contract). I’m just doing my best to be in the best shape when the season rolls around, to be the best version of me that I can be.”

By most accounts Mariota is on a mission, launching himself into the task on several levels.

“Nobody is more proud of what Marcus has done in the offseason than me,” Titans head coach Mike Vrabel told Sports Illustrated recently. “He’s come back stronger, bigger, with greater understanding of what we’re doing offensively, being able to communicate it to players on the field.”

Mariota’s focus and toil have never been doubted. But you haven’t been able to always say that about the Titans’ half of the bargain. The team has had three head coaches, four offensive coordinators, three quarterback coaches not to mention a revolving playbook and constantly changing offensive cast.

In the process, his protection on the offensive line has been sketchy as underlined by 130 sacks in four seasons. And the available arsenal of offensive weapons around him has lagged. When Pro Bowl tight end Delanie Walker went down in the 2018 season opener the paucity of play-making receivers was further exposed on a unit that ranked 29th in passing.

This offseason the Titans made their biggest commitments to date to remedy the situations. They brought in Adam Humphries, a free-agent slot receiver, and used a second-round draft pick on receiver A. J. Brown while signing free-agent guard Rodger Saffold.

Now all that remains is to put it together in a package that fulfills the vision that first brought Mariota and the Titans together.

Reach Ferd Lewis at flewis@staradvertiser.com or 529-4820.