National Football League

'Mr. Irrelevant' Brock Purdy latest QB to flourish in Kyle Shanahan's system

Updated Dec. 17, 2022 4:09 p.m. ET

The NFL has always been dubbed a "quarterback" league due to the impact and influence of the quarterback on the outcome of games.

While a blue-chip quarterback guides the teams that routinely compete for the Lombardi Trophy with top-5 talent, the San Francisco 49ers might debunk that theory again this season by making a title run with a third-string quarterback who is flourishing within Kyle Shanahan's scheme.

Although Brock Purdy — aka "Mr. Irrelevant" — has played well within a small sample size, there is no reason why the former seventh-round pick can't continue to thrive in a system that has also propped up Jimmy Garoppolo, Trey Lance, Nick Mullens, C.J. Beathard and others despite their limitations. The win-loss records might vary, but each quarterback has posted solid numbers and moved the offense effectively when thrust into the lineup as the 49ers' QB1.

How dangerous are Brock Purdy, 49ers?

Emmanuel Acho, Joy Taylor, Dave Helman and Will Blackmon share how confident they are in the Niners with Purdy behind center.

We can debate the talent disparity between each of the quarterbacks mentioned above. Still, it is impossible to deny the impact of the 49ers' supporting cast and quarterback-friendly system on the production of the passers. The "YAC Bros" (Deebo Samuel, Brandon Aiyuk and George Kittle) are masters of "catch-and-run" concepts due to their explosive running skills in the open field. The trio gobbles up yardage after each catch, and their ability to turn short passes into long gains enables the 49ers to feature an assortment of high-percentage throws at or near the line of scrimmage to fuel their passing game.

Studying the 49ers' offense for years, I have always marveled at how Shanahan utilizes bootlegs and movement-based passes with half-field reads to create big plays. The 49ers routinely featured "stretch-boot" (outside zone run/bootleg pass) concepts to move the defense in one direction before slipping out a few receivers to the backside at different levels in front of a quarterback on the move. The layering of the routes (short-intermediate-deep) on one side of the field simplifies the reads to a high school level.

In addition, the threat of the running game lures second-level defenders to the line of scrimmage, which creates enormous windows for the quarterbacks to target pass catchers at short (ten yards or fewer) and intermediate range (10 to 20 yards).

The constant misdirection and deception expose undisciplined defenders while making the game easy for the quarterback. Suppose the passer adheres to the "connect the dots" premise that instructs quarterbacks to take the easiest throw as soon as it is available. In that case, the quarterback will ring up ridiculous numbers with minimal effort.

After watching Purdy shine since stepping in for an injured Jimmy G., the combination of the scheme, supporting cast, and the quarterback's discipline has fueled his impressive production and performance. The rookie has posted a 69% completion rate with 7.2 yards per attempt average and a 6:1 touchdown-to-interception ratio in his past three games.

Those numbers are strong for a starting quarterback, particularly a lightly regarded rookie drafted in the seventh round. Purdy's poise, patience and discipline have fueled the 49ers' stunning offensive execution under his direction. He has resisted the urge to make "hero" throws while sticking to the script from the coaching staff.

Against the Seattle Seahawks on Thursday, Purdy colored inside the lines while completing 17 of 26 passes for 217 yards with a pair of scores. The rookie opened the game with 11 straight completions, including a 28-yard touchdown to Kittle in the first quarter. Purdy joined Aaron Rodgers as the only quarterbacks since 1950 to have a passer rating of at least 115 in each of his first two starts, per ESPN.

Given how the system has transformed average players into Pro Bowlers (SEE: Kirk Cousins) and Pro Bowlers into MVPs (SEE: Matt Ryan), the efficient play from Purdy is a testament to Shanahan's play designs, call sequencing and personnel deployment. The offensive wizard has worked miracles in the past and is waving his magic wand over Purdy's head.

With a division title under wraps, the 49ers' offensive architect could claim a Super Bowl ring with a QB3 who looks like a star in the system.

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Bucky Brooks is an NFL analyst for FOX Sports. He regularly appears on "Speak For Yourself" and also breaks down the game for NFL Network and as a cohost of the "Moving the Sticks" podcast. Follow him on Twitter @BuckyBrooks.

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