How did Sam Darnold’s route distribution change post-injury?

By Michael Nania@Michael_Nania Jul 29, 2019, 11:39am EDT

Recently I took a look back at Sam Darnold’s 2018 season and chopped up the differences in his production based on route type and field side.

Today, we’ll be comparing the changes in Darnold’s production between his four-game hot stretch to finish the season and his first nine games of the year.

First, let’s take a look at the differences in Darnold’s passing yards per game by route type, between his pre-injury and post-injury stretches.

The first thing I noticed was the huge dip in screen yardage. The Jets drastically decreased their reliance on screen plays over Darnold’s final four games. Darnold attempted 2.6 fewer screens per game and completed 2.1 fewer per game, each decrease his biggest of any route. The dip in completions was over three times larger than that of any other route. I think it showcases an increase in the trust that the coaching staff had in Darnold later in the year, especially following his chance to sit back and reflect for a few weeks.

Darnold saw huge bumps in his production on the corner, out, and curl routes. Not only did he see huge bumps in both his volume and accuracy on those routes, but the average depth of his completions increased on all three as well. Darnold’s connection with Chris Herndon and Robby Anderson on these routes looked like the beginning of something potentially special.

Next, let’s look at the change in Darnold’s completion percentages, adjusted for my drop counts.

Post-injury, Darnold improved his accuracy on 11 of the 15 route types that I tracked. The lone exceptions were all deep routes — the cross, post, and go routes. Darnold completed 4 of 11 crossing routes with one drop over his first nine games, but attempted only two of those over the final quarter of the season, with both falling incomplete. The small sample size leads to the seemingly huge percentage dip.

For the go and post routes, Darnold tried a nearly identical diet of attempts, but on each route, he fell just one accurate pass short of posting an accuracy rate nearly the same as his pre-injury marks.

Otherwise, Darnold improved across the board, and by a large amount in many cases. He was much more sound with his consistency on all of his underneath routes, seeing accuracy jumps of at least 10% on checkdowns, screens, flats, and drags.

In the intermediate range, Darnold dramatically improved his efficiency on the comeback and corner routes. Pre-injury, on those two routes, he completed 6 of 18 attempts for 90 yards and five first downs (one drop). When throwing those two routes post-injury, he completed 9 of 12 attempts for 150 yards and seven first downs (one drop).

Finally, here’s a look at the change in Darnold’s distribution of attempts.

What stands out first is the amount of red on the underneath routes. Darnold certainly did get more aggressive in December, while the Jets lessened the amount of manufactured calls. Reflecting this, Darnold saw a jump on his average attempt depth post-injury, leaping from a solidly above average 8.58 yards over his first nine games to a crazy high 9.98 yards over his final four games.

Here’s another tidbit that further compounds the decrease in underneath reliance shown by Darnold down the stretch. Over his final four games, Darnold saw an incredibly low 34% of his passing yards generated after the catch. Ideally, you would like to see that number around the league average 50% mark that Darnold posted pre-injury (Tom Brady and Patrick Mahomes had 52% of their yards after the catch last season). However, it’s good to know that Darnold’s quality late-season production was largely his own doing. He didn’t post better numbers because he lucked into a bunch of dump-offs going 50 yards — he put up those numbers with his arm alone.

Contrary to his decreases in other underneath throws, Darnold threw more checkdowns, which I was happy to see. Early in the season, Darnold often attempted ill-advised downfield throws while there was a high-floor checkdown opportunity available. On a recent episode of One Jets Drive, Sam himself discussed how he needed to improve on his ability to understand when the dump-off was the right play.

It seems that this certainly was something he improved on down the stretch. I had Darnold throwing 0.6 more checkdowns per game over the final stretch — a seemingly small number, but his fourth-largest increase of any route. His post-injury checkdowns were also more fruitful, as they averaged 9.3 yards per attempt versus 5.7 yards per attempt pre-injury.

The out and curl routes became Darnold’s best friend. He threw a combined 3.5 more of those per game post-injury than he did pre-injury. His efficiency on those routes increased with the heightened volume, as Darnold threw for 7.2 yards per attempt and a 39% first down rate on outs and curls post-injury versus 6.1 yards per attempt and a 30% first down rate pre-injury. An increase in depth on those throws accompanied his increase in efficiency, as Darnold’s average attempt distance rose by 1.0 yard on the curl route and 1.4 yards on the out route.

When Darnold was clicking this season, the curl route was a part of it. In his four games with over 250 passing yards, Darnold threw for 15 first downs on curl routes, or about 3.8 per game. In his other nine games, Darnold threw for only seven firsts on curl routes, or just 0.8 per game.

Here is a complete look at the statistical changes in each of Darnold’s route types over his post-injury stretch versus his pre-injury stretch. A positive number represents an increase, a negative number represents a decline.