Can Marcus Mariota be a real threat to Derek Carr’s starting job?

The Marcus Mariota era in Nashville is over. Let the Marcus Mariota era in Las Vegas begin.

The Raiders swooped in at the start of free agency to come to a two-year contract agreement with the former Titans quarterback. In four months, Mariota has gone from losing his starting job to Ryan Tannehill to battling for a new one against Derek Carr.

That gives the club two relatively well-known passers who’ve failed to live up to the high expectations of early-career success. Carr has been unable to recapture the form that made him an MVP candidate while going 12-3 as a starter in 2016. Mariota was a Heisman Trophy winner who threw four touchdowns in his NFL debut, then later beat the Chiefs in a playoff game by throwing a touchdown pass to himself. Yet he still couldn’t hold off Tannehill in his final season with Tennessee.

It may seem a little strange that Jon Gruden buttressed one decent, slightly disappointing young veteran with another. It’s even less orthodox that he invested $29 million in salary cap space — $21.5 million for Carr and $7.5 million for Mariota — to an unsettled quarterback situation. A closer look suggests there are a few ways this new signing can be an upgrade for the Raiders ... and a few reasons why Mariota may not be.

From a statistical standpoint, Carr is the more efficient passer. He’s averaged more yards per game, a higher completion rate, lower interception rate, and better passer rating than his new teammate. When you dig down beyond those surface numbers, however, Mariota begins to build a case as to why he can threaten Carr’s spot atop the depth chart.

First, let’s talk about the major issue both good, not great quarterbacks will have to face in 2020. If Gruden is looking to stretch the field vertically, he may wind up frustrated with both his options.

Neither is known as a deep-ball aficionado, but few quarterbacks have checked down to short passes quite like Carr has in his NFL career. His average pass in 2019 traveled just 6.2 yards past the line of scrimmage, per SIS. That’s the second-lowest throw distance any starting quarterback has ever posted over a full year since 2015, besting only Sam Bradford’s 2016 season in Minnesota.

Mariota has typically been more willing to take risks downfield, but those attempts have tapered. His average throw depth declined in each of the past three seasons, bottoming out at 6.7 yards last fall in a career-low six starts. That doesn’t mean these passers can’t lead successful aerial offenses — both Jimmy Garoppolo and Drew Brees clocked in at 6.3 yards per pass in 2019. But while 7.1 percent of Brees’ passes ended in touchdowns, only 4.1 percent of Carr’s did. Mariota’s touchdown rate the past three seasons is a scant 3.3 percent.

This all paints a telling picture of Carr as an accurate short-range passer happy to take what defenses give him without forcing the ball downfield. Mariota will air it out more, just not as efficiently as the man he’ll battle for snaps in Las Vegas:

They’ve got similar tendencies when it comes to throwing the ball, but Mariota has done more with less, at least from a supporting cast standpoint. Carr had solid wideout presences in both Amari Cooper and Michael Crabtree, who each earned 370 of his targets as Raiders over the course of his six-year career.

Conversely, Mariota’s top four most targeted teammates in Tennessee were Delanie Walker (305), Corey Davis (176), Rishard Matthews (173), and Tajae Sharpe (124). While Carr eventually inherited a bad WR situation, Mariota was drafted into one that never got much better.

They’ll have an even playing field in 2020, though Gruden and general manager Mike Mayock will have to upgrade their receivers to better complement breakout tight end Darren Waller. The Raiders’ WR/TE corps behind him is currently led by Tyrell Williams, Zay Jones, Nelson Agholor, Hunter Renfrow, and a soon-to-be 38-year-old Jason Witten. With two first-round picks and a deep class of wideout talent available in this year’s draft, that group is likely due for some reinforcements come April.

The one area where Mariota is undeniably the better option for the Raiders is on the ground. His legs add an extra dimension when pressed to avoid the pass rush or dump the ball to a checkdown target. In 63 games, he’s rushed for 1,399 yards and averaged 5.8 yards per carry while running for 11 touchdowns and 87 first downs.

Carr is no statue, but he can’t replicate that kind of performance. His most notable scrambles may be the two times he managed to dive for the pylon and then fumble the ball out the back of the end zone. In fact, Mariota has fumbled less (0.52 times per game) than Carr (.55) despite being counted on to carry the ball more often and being sacked nearly twice as often (8.1 percent sack rate vs. 4.9) as the incumbent Raider QB.

That sack rate indicates the Titans were victim of deficient line play. Although blocking was a problem — especially in 2019 — Mariota’s tendency to hold on to the ball shares some of the blame.

Carr has been better about getting rid of the ball, thanks in part to his ability to progress through reads quickly and dump passes to short-range targets. Per NFL’s Next Gen Stats, 2019 was the first season he averaged more than 2.55 seconds in the pocket before firing off a pass. Mariota, comparatively, has averaged 2.74 seconds in the pocket over the last four years.

Carr is the quarterback who works through his progressions and makes smart choices, even if they result in meager gains. Mariota is a little bit more of a risk taker — partially because he can pull the ball down and run with it, and partially because he’s lacked the high-end weapons that can give him open windows on a consistent basis.

Carr will remain the presumptive starter until the Raiders say otherwise. That doesn’t mean Mariota can’t do to Carr what Tannehill did to Mariota.

Mariota will have a shot to run the Raiders’ offense if he can learn the playbook, something Gruden admired about him dating back to the quarterback’s college days and the coach’s time as an analyst. Gruden once said his latest signing behind center “could be really one of the great quarterbacks in the future of the NFL.”

That didn’t pan out in Tennessee. Mariota will have to prove he can provide more than Carr’s high-efficiency, low-impact passing attack to make it work in Las Vegas.