Everyone hits the wall at some point.

Mac Jones has been the best rookie passer of the 2021 NFL Draft class by any measure or metric: While he started the yeaer playing it short, the Patriots QB has grown into one of the better all-around passers in the league in a very short time.

But, in recent weeks, Jones has seemingly hit the rookie wall: Following a seven-game winning streak, the Patriots QB has scuffled in the last two games, losses to the Colts and the Bills. He’s thrown two touchdowns to four interceptions and has been uncharacteristically inaccurate, with a 51.95 completion rate in across both matchups.

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While it’s normal for rookies to hit a wall, former Patriots quarterback Matt Cassel provided a bit more context to why Jones may be struggling:

“There were times when I felt he was flustered in the pocket. His feet weren’t set,” Cassel said on the Patriots post-game show. “So, there’s this thing going on with his mechanics, his technique. He’s getting a little bit flustered where he’s just missing some of these wide receivers.”

It certainly makes sense: Quarterbacks, especially young ones, are usually less-good against pressure and blitzes, and that’s been the case with Jones in 2021. Pro Football Focus has him graded with an 82.9 overall passing grade with a 71.9 percent completion rate when he has a clean pocket.

That number drops to 57.7 grade and a 54.3 percent completion rate when he’s under pressure. That grade is still good for 11th in the NFL, so it’s not as damning as it may seem. 

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There’s a little bit more context to it, too: Jones is pretty good when facing the blitz (69.7 passing grade), so where he’s been hurt the most is against a traditional four-man rush. 

Jones, a garden-variety pocket passer, has been heralded for his footwork, pocket manipulation and quick processing ability, but as it turns out, getting pressure on him is the key to throwing off his mechanics, and therefore, his game.

Getting pressure on a quarterback could affect him? Who knew?