The Tennessee Titans finally pulled the plug on the Marcus Mariota era. Though wins and losses don't paint a full picture of his tumultuous final season in baby blue, it's hard to look past Tennessee's ability to win games with and without Mariota as the starting quarterback. In six games with Mariota as the starter, the Titans won just twice, with one of those wins being against a pitiful Atlanta Falcons team. In the following six games with Ryan Tannehill as the starter, the Titans won five times, falling only to the Carolina Panthers with a 30-20 final score.
Tannehill was traded away from a rebuilding Miami franchise after years of not being able to make it work with him at the helm, yet he has been arguably the most effective quarterback in football since being named the starter in Tennessee. Mariota was given every opportunity to succeed in this offense, but hasn't managed to make it work in years. It's been night and day between the Miami cast-off and the former No. 2 overall pick.
Before diving into all of why Tannehill has been a godsend compared to Mariota, it's worth dissecting where the two aren't actually any different. Tannehill has been a far more effective quarterback overall, that much is true, but some of the issues that plagued Mariota have remained through the quarterback change. It would be disingenuous and incomplete to lift up Tannehill as having solved all of the Titans' issues by himself.
The obvious similarity between the two is how they manage their time in the pocket. Over the course of both of their careers, neither player has been particularly impressive in managing the pocket or understanding that they need to get the ball out on time. Among the 35 quarterbacks with at least 40 games started since 2012 (Tannehill's rookie season), Mariota and Tannehill rank 29th and 30th, respectively, in Pro Football Reference's sack index, which simply accounts for how often a quarterback is sacked relative to league average. In 2019, specifically, Mariota has been sacked on 13.6% of his dropbacks, compared to Tannehill being sacked on 12.0% of his dropbacks. They hold the two worst sack indexes among quarterbacks with at least six starts this season.
Along the same lines, Mariota and Tannehill are near-identical in how long they hold the ball on average. Per NFL Next Gen Stats, Mariota's time to throw in 2019 is 2.84 seconds, which ranks 12th-highest among 38 qualifying quarterbacks. Tannehill trails just behind at 2.81 seconds, earning him the 16th-highest mark in a tie with Russell Wilson. Considering Tennessee ranks respectably at 13th in pressure rate, according to Sports Info Solutions (subscription required), it's quite damning of Tennessee's two quarterbacks that they get sacked at the absurd rate that they do.
Tannehill's other notable similarity with Mariota is his deep passing. While Tannehill has thrown a few memorable deep passes this year, such as his 40-yard strike to Khalif Raymond last week to stick a dagger into the Colts late in the fourth quarter, the consistency isn't there. In fairness, Tannehill has been a questionable deep passer for his entire career, so it was never the expectation for him to be a high-end deep passer when he took over the reigns.
What has allowed Tannehill to ascend to a level far beyond Mariota's despite some of their similarities is his ability to work the most valuable part of the field: the intermediate area. While deep passing holds the highest chance for a big play and short passing generates a stable baseline for an offense, intermediate success is where quarterbacks -- or passing offenses, rather -- separate themselves from one another. Tannehill has proven himself capable of reading and accurately throwing a number of different intermediate concepts in his handful of starts.
Y-cross isn't a particularly complicated concept for a quarterback to read, but Tannehill does well to cross his T's and dot his I's on this play. To the boundary, Tennessee deploys a 5-yard out from the slot and a straight vertical route from the outside receiver. The 5-yard out to the short side of the field is the easiest throw Tannehill can make on rhythm here. Tannehill goes through his short dropback looking for the 5-yard out and draws his arm back to throw as soon as his back foot hits the ground. Even if Tannehill doesn't actually end up throwing it, beginning his draw at the top of his dropback is a good time-saver for quick passes. In this case, Tannehill sees Carolina's slot defender and weak hook defender swarm to the 5-yard out before fully committing to the throw. Tannehill then immediately turns his attention to the slot receiver coming across the middle from the other side of the field and fires after resetting his feet. The pass hits the receiver right in stride to bail Tennessee out from deep in their own territory.
The former Dolphins quarterback showed off this same vision and smooth process on a deeper concept against the Chiefs. In the previous play, Tannehill got the ball out to the second-deepest possible target. In the following clip against the Chiefs, Tannehill throws it to his second-shortest possible target. The actual throw distance isn't really any different, but the shift in ideas between the two concepts forces Tannehill to approach them differently.
Tennessee rolls out a verticals concept that seems to give the field-side (left) slot receiver the option to bend inside depending on the leverage of the safety. This is a common four-verts adjustment, but it's worth noting before getting into the rest of the play. Upon receiving the snap, Tannehill trots back with his eyes focused on the vertical down the left sideline. The safety over the left hash bails deep and to the sideline to cover his half-field assignment. Tannehill realizes the safety is bailing deep and away from the hashes, so he comes off his initial read to move on to the slot receiver bending over the middle. Again, the pass hits the receiver in the perfect spot, this time allowing him to find the end zone.
Neither of the past two plays are particularly straining reads or throws for an NFL quarterback, but they weren't plays that Mariota was consistently making. Be it processing a tick slowly, hesitating to throw over the middle, or general inaccuracy, Mariota just wasn't executing on intermediate throws the way Tannehill has been. Tannehill has been on fire in the 10- to 20-yard range.
Some of the success can be attributed to the scheme and play calling. Offensive coordinator Arthur Smith was quietly putting together a nice, cohesive offense early in the season, but plays just weren't being executed. Tannehill is now executing on those previously missed opportunities, especially on play-action.
To be specific, Tennessee has been excellent with play-action out of heavier personnel from under center. While it goes against the data to say a team's running game "sets up" the play-action, it's tough to separate how effectively Tennessee runs iso and power, both of which feature the fullback leading the way as a blocker. Over the past three games, running back Derrick Henry has crested the 150-yard mark largely using these run concepts. Intuitively, it makes sense that defenses might be more willing to come up to play the run when Henry is playing so effectively on those concepts.
Again, there is nothing new or fancy about any of this. Even without going all the way back to the "glory days" of hard-nosed iso running and heavy-personnel under-center offenses, we can look at the Los Angeles Rams' offense in recent years. Their entire passing identity revolves off of play-action from under center, particularly plays like the two above in which the quarterback throws (almost blindly) to the skinny post cutting over the middle. Though a quarterback doesn't need to be the sharpest to make these plays work, they do need to have fairly impressive arm strength and a quick enough trigger to throw before the linebackers can regain their depth.
Tannehill's arm talent and boldness have permeated throughout the rest of his game as well. Per Next Gen Stats, Tannehill throws into tight windows 21% of the time, which is significantly higher than Mariota's 15.1%. Likewise, Tannehill's average depth of target (8.9) is more than a full yard deeper than Mariota's (7.2). Most reasonable people would expect Mariota to have the higher completion percentage given those numbers, but Tannehill's completion percentage is more than 10 points higher.
Sometimes fixing a machine is as simple as replacing one faulty gear. Mariota too often sputtered and stalled out for Tennessee's offense to move the ball. Through Week 6, before Tannehill took over, the Titans were 28th in drive success rate and 30th in points per drive. Since the switch to Tannehill, Tennessee ranks fifth and sixth in those same categories. The Titans have also gone from the third-worst three-and-out percentage to the sixth-best. In almost every way, the Titans offense has morphed into one of the league's best not due to exceptional quarterback play or any game-breaking schematic development, but because the system is being executed in a way that it wasn't before.
At some point, this absurd run from Tennessee has to come to a stop. Henry can't keep putting up over 150 yards each game and it's tough to imagine Tannehill has suddenly bloomed into an elite quarterback in his eighth professional season. When it does begin to slow down, however, there should be no complaints about them being an average or slightly above average unit. The passing offense under Mariota was anemic in a way that actively held the team back, whereas Tannehill's guidance of the offense at least provides Tennessee the means to compete in every single game.