49ers’ Age on the Offensive Line: “Theory of 150” vs 50 Starts

You've heard all of the clichés about line play and football. All the talk of "the trenches" and how "winning football starts up front" can sound like white noise after a while, but that doesn't make any of the statements false. If you pay much attention to offensive line play, or you regularly listen to or talk football with someone who is passionate about offensive line play, you have undoubtedly heard the argument that you don't need the best offensive linemen to field the best offensive line. While it certainly helps to assemble the unit out of large, strong, athletic, aggressive, technically-sound monsters, an offensive line that communicates well, blocks in combination well, and seamlessly transitions to provide help where needed, tends to perform very well. All of those group traits tend to be enhanced with increased familiarity, leading to the assertion that offensive lines must play together for some time before they can play together well.

49er fans will remember the criticism falling on the 49ers' offensive line in 2011, when Joe Staley felt the need to declare, "We don't stink." The 49ers were struggling to protect the quarterback and open rushing lanes and were absorbing much of the blame for the offense's early struggles, but Staley asserted that the issue was temporary. He was right. By the end of the season, the 49ers boasted one of the best and most physical offensive lines in football. They had to grow accustomed to one another and their new head coach's blocking scheme, in order perform well as a group.

The question must present itself: How much time does it take? The answer is tough and ambiguous, as an offensive line unit will generally perform better within the confines of one season, as long as they stay relatively healthy, as evidenced by the 2016 49ers. The offensive line had some trouble making holes for most of the first half of the season. After enjoying a dominant coming out party against the LA Rams to start the season, the 49ers found rushing yards hard to come by. From week 2 through week 10, the 49ers averaged roughly 115 rushing yards per game. As the season has progressed, the offense has had more success on the ground. From week 11 through week 15, the 49ers averaged just over 160 rushing yards per game. More importantly, 49ers running backs were gaining more yards before contact, meaning that the line was blocking enough defenders to allow the backs to advance deeper into the defensive backfield before a defender could get close enough to touch them.

So is the answer to the "how long?" question on the season? Here's where the answer gets ambiguous. Of course, you should expect a line to play better as a group at the end of a season than you would at the start, but that doesn't truly optimize their play. A line needs more time than that, including multiple offseasons together, to slow down and talk through complicated adjustments and last second, pre-snap scenarios. They need thousands of repetitions to make those adjustments second nature, so their bodies perform their jobs as an extension of their athletic instincts, rather than as the result of a deliberate, intentional thought. They need time to adapt to the strengths, weaknesses, and idiosyncrasies of the blocking technique employed by the man adjacent to them on each side. They need to know exactly under which conditions their combination blocking partner will leave the block to pick up a second defender. Knowing when and how their comrade will move off of the block allows that man to take sole control of the block without losing the control and momentum that the double team generated. Guessing poorly can allow one or more unblocked defenders to reach the ball carrier at the point of attack. Communicating when a teammate receiving help in pass protection will suddenly lose that help because the defense has presented a new pass rusher to a previously unthreatened gap is vital to maintaining a clean pocket for the quarterback. Lines who have played together long enough make those transitions without a spoken word, because they see the same strengths and weaknesses in their own protection, and they recognize the same threats presented by the defense.

FIFTY. That's the widely accepted number of starts that one offensive line unit must have together before they can be expected to regularly perform as one synchronized unit that is much more effective than the sum of all their separate parts. That implies a minimum of two complete offseasons together (if one of the starters was a rookie in the first season, he likely would not have had a full offseason with the team), along with at least three seasons to play together. In a perfect world, where your team reaches the playoffs each year and your line stays healthy, you reach that magical number fifty in the run-up to the playoffs near the end of the third season. More commonly, accounting for injured starters and non-playoff seasons, it happens in four to five seasons. While it is unlikely that many offensive line units will ever reach and play together beyond 50 starts, that mark remains a target for continuity and cohesion for the most chemistry-dependent unit in football.

Do the 49ers have that kind of time? Where will they be in four seasons, and will the current starters still be the best options as starters? In 2012, ESPN's John Clayton discussed a theory he started studying and compiling data on, back in 2007. He called it the "Theory of 150," and it simply declares this: Any offensive line unit whose aggregate age exceeds 150 years (and has three or more starters over 30 years old) can expect a significant decline in play over the course of the season. As more data supported the theory, teams started making moves to avoid getting too old on the line. Replacements were drafted to develop in reserve for 30-year-old tackles, even when they were still playing well. Young guards were cross-trained at center and trained more diligently on executing line calls, in anticipation of the old man on the line suddenly hitting the wall or suffering a significant injury.


The 49ers' preferred starters currently have an aggregate age of 136 this season, and it would reach 141 next season. With Joshua Garnett and Trent Brown installed as new starters this year, and Joe Staley and Daniel Kilgore missing starts due to injury, the starting unit only accrued seven starts together, meaning they would need to stay together for at least three more seasons to approach fifty starts and enjoy the performance benefits of seamless cohesion. In three seasons, the aggregate age of the unit would be 151 years, and Staley, Kilgore, and Zane Beadles would all be well over 30 (35, 32, and 33, respectively). What's more concerning is that next year, Staley, Beadles, and Kilgore will all be 30 or older. The aggregate age of the unit is decreased significantly by the status of Garnett and Brown as starters (22 and 23 years old, respectively). While Staley has not demonstrated any sharp decline in his play, he has been less consistent than in years past, and he has missed more snaps due to injury. Beadles has never missed a start due to injury, but Kilgore has never started 16 games in his three seasons as a starter.

It's unlikely that all of the same starters will be in place three years from now, so will the 49ers continue to mix and match as necessary to cobble together an offensive line that approaches functionality, or will they get younger and risk poorer play in the short term to reach? There are several options to get younger and preserve a meaningful veteran presence along the line, some of which I'll touch on here. With each option, please bear in mind that the aggregate age of the unit after three years (the earliest they could reach 50 starts together) would be ten years higher than the 2017 aggregate age I've listed below.

KEEP STALEY

The first few options allow the 49ers to keep Joe Staley at LT. Although he's the oldest starter on the OL, he is the unit's only Pro Bowler, the leader of the group, and he still plays at a high level. It is difficult for any team to make a change at LT when the current starter can handle the job well. Zane Beadles has surprised by performing well at center in his first two opportunities at the position. Replacing often-injured Daniel Kilgore (29 years old) at center with Beadles (30) allows the team to keep the two most vocal veteran leaders on the unit, while presenting an opportunity to get younger at a unit by bringing in a new starter at guard, the least difficult position for young players to step in. The 49ers could promote current injury replacement Andrew Tiller (27 years old) to full-time starter, draft a replacement (likely 21-22 years old) or bring in a stud free agent like the Bengals' Kevin Zeitler (26 years old) to fill the guard position with a strong NFL performer. Zeitler has been a dominant right guard in the NFL, and moving him into that spot allows Garnett to return to the left guard spot he played in throughout his decorated college career.

Staley-Tiller-Beadles-Garnett-Brown 2017 Aggregate Age: 139

Staley-Garnett-Beadles-Zeitler-Brown 2017 Aggregate Age: 138

Staley-Rookie-Beadles-Garnett-Brown 2017 Aggregate Age: 134

REPLACE STALEY

This option is hard for me to consider. Joe Staley is one of my favorite 49ers, and there has not been a dramatic drop-off in his play, though his athleticism and strength appear to have diminished slightly, he continues to improve his technique and offset his physical losses with strategic gains. He is a leader on the offense and the most-trusted veteran voice in the offensive line meeting room. He is also the oldest starter on the unit, he's suffered nagging injuries, and his decline could be sudden if he hits a veteran wall. Bill Walsh kept the 49ers competitive for years with the philosophy that it was better to let an aging vet leave two years too early than it was to keep them two years too long, and the current New England Patriots stay competitive in a large part due to Bill Belichick's ruthless employment of that strategy.


With Zane Beadles emerging as a solid performer at center (a position that ages MUCH more gracefully than tackle), and as a loud leadership voice that rallied the offense to victory in LA, some of the concerns about getting too young too fast could be alleviated. Trent Brown is a physical freak whose length, size, strength, and agility gives the potential to not only start, but to physically dominate as a left tackle in the NFL. He has filled in for Staley as a capable left tackle with the tremendous potential to improve, and moving him to the left side could allow the 49ers to move Garnett to left guard with Brown, preserving an impressively powerful run blocking duo. That said, moving Brown to left tackle would open up a new space to fill at right tackle, either with one of the current rookies (John Theus (22), who started at RT in LA, or Fahn Cooper (23)), a drafted rookie like Wisconsin's Ryan Ramczyk (21), or a free agent addition like Ryan Schraeder or Riley Reiff (both 28 years old).

Brown-Beadles-Kilgore-Garnett-Theus 2017 Aggregate Age: 132

Brown-Beadles-Kilgore-Garnett-Schraeder/Reif 2017 Aggregate Age: 138

Brown-Beadles-Kilgore-Garnett-Ramczyk 2017 Aggregate Age: 131

Brown-Tiller-Beadles-Garnett-Theus 2017 Aggregate Age: 129

Brown-Garnett-Beadles-Zeitler-Theus 2017 Aggregate Age: 128

Brown-Garnett-Beadles-Zeitler-Schraeder/Reif 2017 Aggregate Age: 134

Have an opinion? Place your vote in the poll down below, or let me hear it in the comments section.

Poll

• How would you prefer the 49ers get younger on the offensive line?
• Replace Kilgore
  44%
• Replace no one (don't worry about getting older, get more consistent with the current group)
  28%
• Replace Staley and Kilgore
  14%
• Replace Staley, Beadles, and Kilgore
  6%
• Replace Staley
  4%
• Replace Beadles
  4%
• 218 votes