In Week 4 of the 2018 season, Rams quarterback Jared Goff accomplished something that had happened just 28 previous times since 1950. Completing 26 of 33 passes for 465 yards, five touchdowns and no interceptions, Goff became just the 23rd quarterback in that span with 20 or more passing attempts in a game to compile a perfect passer rating of 158.3. The list of players who did it before is just as loaded with one-time flukes as it is with lead-pipe lock Hall-of-Famers (Jeff Blake? Kerry Collins? Craig Erickson? Vince Evans?) but given Goff’s overall progression since Sean McVay was hired as the team’s head coach before the 2017 season, this looked like the highest possible distillation of Goff’s progression to the top of the NFL charts.

But as they say, life comes at you fast. Over the Rams’ last three games, Goff has been the second-worst quarterback in the NFL from a statistical perspective, behind only Mark Sanchez, a name from the distant past who rushed in (and rushed right back out) in a failed attempt to clarify Washington’s desperate quarterback situation. From Weeks 13-15, including Sunday night’s 30-23 loss to the Eagles, Goff has completed just 72 of 131 passes (a 54.96% completion rate) for 726 yards, one touchdown and seven interceptions.

The advanced stats are even worse, and show the glaring difference in Goff’s game in that recent time. From the start of the season through Week 12, per Pro Football Focus, Goff was one of the league’s best deep passers, completing 24 of 45 passes for 812 yards, seven touchdowns and two interceptions on balls thrown 20 yards or more in the air. Since Week 13, he’s completed just two of 13 such passes for 59 yards, no touchdowns and three picks.

And if you watched that loss to the Eagles and wondered if Goff was throwing the ball away at an unusual rate, you’re onto something—in his first 12 weeks, Goff threw the ball away 27 times—second-highest in the league, but nowhere near NFL leader Aaron Rodgers (47). Over the last three games, Goff has thrown the ball away—essentially given up on a play because he doesn’t like what he sees—10 times, tying him with Bills rookie Josh Allen for the league lead.

And Goff has absolutely fallen apart on long-developing plays. Through the first 12 weeks, he completed 148 of 239 passes and threw 15 touchdowns to four interceptions on plays where he was in the pocket 2.5 seconds or longer. Over the last three weeks? 47 completions in 87 attempts, one touchdown and all seven of his interceptions. And over that time, Goff’s percentage of plays in which he’s in the pocket 2.5 seconds or longer has actually increased—from 65.9% to 69.1%.

When looking at the reasons for Goff’s sudden malaise, his relative inefficiency on long-developing plays may have an enormous hidden factor—more than before, defenses are presenting Goff with different coverages, forcing him away from easy reads (a hallmark of his success under McVay in a general sense), and making him succeed against coverages that reveal themselves later in the down.

Goff said as much after the Eagles loss.

“Teams are doing different things to us. Teams are trying out different things, and we just need to find a way to respond.”

Goff also talked about how “I feel like I’ve grown and learned and made strides in a positive direction regardless of what has happened,” but the tape tells an entirely different story. While Goff has shown growth as a player from his nightmare rookie season of 2016 to now, he had also relied heavily on McVay’s schematic constraints, and those schemes aren’t working as well for the Rams as they used to.

Let’s start this study with a few plays from when things were working.

On this 19-yard touchdown pass to Cooper Kupp (No. 18), Goff has to hit Kupp on a crosser, and he has to get the ball over cornerbacks Trae Waynes (No. 26) and Mike Hughes (No. 21). The right-to-left motion of running back Todd Gurley (No. 30) does freeze safety Anrew Sendejo (No. 34), but that doesn’t help Goff in this case. He still has to make a near-perfect throw to get this touchdown, and he does.

Kupp was lost for the season in Week 10 with a torn ACL, and his absence is a factor in Goff’s recent lack of production, but Kupp certainly wasn’t the only receiver benefitting from Goff’s tight-window accuracy against the Vikings. Here, on a vertical route up the numbers, you see Brandin Cooks (No. 12) using his speed to lift Waynes upfield, and Goff makes a throw with excellent timing and velocity to match Cooks’ downfield acceleration.

This 40-yard touchdown to tight end Gerald Everett (No. 81) was the deciding score in the Rams’ 54-51 Week 11 barnburner over the Chiefs. This touchdown is a byproduct of another McVay staple—create mismatches through formation and receiver distribution and count on your quarterback to recognize where those mismatches will be. The Rams bedeviled Minnesota’s Anthony Barr with this over and over in Week 4, and this time, McVay’s huckleberry is Kansas City safety Daniel Sorenson (No. 49), who simply can’t keep up with Everett down the boundary.

And even against the Lions in Week 13 (the week the trouble for Goff started), he was still taking advantage of favorable matchups. This eight-yard touchdown pass to Robert Woods (No. 17) in the second quarter is the last touchdown pass Goff has thrown this season. Pre-snap, Woods’ motion reveals that the Lions are playing man coverage when cornerback Darius Slay (No. 23) moves with Woods to the three-receiver side. Then, you see the Lions tightening their defense as if they’re expecting a run, and Woods runs a drag route through the vacancy left by that perception. All Woods has to do is beat Slay, and all Goff has to do is wait for him to do it.

But in Goff’s first throw of the Lions game, you could see the issues starting to pop up. When Cooks motions from left to right, Detroit shows zone coverage. As is often the case, the motion receiver is Goff’s first read, but linebacker Christian Jones (No. 52) hangs with Cooks as Goff doesn’t expect him to, and Goff isn’t able to re-set his vision or get out of the pocket before the pressure comes in. The result: An incomplete pass, and the start of a worrisome trend. While Goff had second-level reads open over the middle, he couldn’t take advantage.