49ers Preseason Observations: Four Things to Watch on the Offensive Line

It's indeed refreshing to read about the San Francisco 49ers dealing with positions other than quarterback during training camp. Since July 26, the battle for left and right guard has dominated my attention.

It didn't take long for veteran Laken Tomlinson to secure the left guard position; right guard, however, has turned into Shakespearean tragedy.

Third-year guard Joshua Garnett hasn't practiced since July 28 due to another knee injury and will not participate in the August 9 preseason game. His absence has allowed Jonathan Cooper, Erik Magnuson, Mike Person, and JP Flynn to compete for the first-string spot.

Even though it's the first preseason game, there are plenty of factors to observe and evaluate with the offensive line. Here are four suggestions for Thursday's game.

Pass Protection

Last year, the 49ers had games when the pass protection was atrocious, and other games when the offensive line looked like it was a finely tuned machine. In fact, when the offensive line kept the pocket tidy, quarterback Jimmy Garoppolo earned a 110.1 passer rating. (Pro Football Focus)


An inconsistent line can make or break a football team, and while last year's roster had talent gaps, a football team with five men up front who can communicate and protect can be the difference between an eight-win season and a 10-win season.

The 49ers enter this season with an offensive line that could end up being in the top ten. However, only Joe Staley and Tomlinson have significant experience in Kyle Shanahan's offense.

Four preseason games are critical for the starting linemen to communicate and learn to work together, even without a true starter at right guard. Indeed, the first string linemen will only play a series or two together, but it's essential they begin to bond and communicate the right protections at the right time.

Individually, take a look at how new center Weston Richburg works with his guards to clear out the A- and B-gaps and set up the best protection for intermediate or long passes.

Keep in mind, Richburg was playing excellent football last season before a concussion landed him on injured reserve for the remainder of the season. In 162 pass snaps, Richburg only allowed two hits, one hurry, three pressures, and did not allow a sack. (Pro Football Focus)

Who's Getting to the Second Level?

Shanahan loves calling outside zone runs. Of course, his run playbook also contains powers, leads, traps and tosses. But his staple running play is an outside zone.

Here's how to spot it: If a run is going right, an offensive lineman must recognize if he is covered or uncovered. If he's covered, he blocks the defender in front of him. If not, he could assist with a block to his right and then move to the second level to pick up a linebacker.

Years ago, it made sense to put 350-pound brick walls on the offensive line. There was little need for these men to move vertically, so long as he could pull left or right and provide time for the quarterback to throw.

An outside zone system asks linemen not only to be brick walls but to be quick and focus on technique.

Throughout the game, watch for outside zone runs and which linemen are making it to the second level and clearing linebackers from potential running lanes.

Running Back Interaction with the Offensive Line

I remember a moment last season watching the offensive line and former running back Carlos Hyde execute a 3 Jet pass protection. You'll notice 3 Jet when four offensive linemen slide to the strong side, while the weak side tackle and back pick up any pesky blitzing opponents on the opposite side. 2 Jet protection is the reverse; four linemen slide to the weak side and the tackle and back clean up the strong side.

Shanahan's system requires backs to be able blockers, along with quick runners and sure-handed receivers. I'm curious to see if second-year back Matt Breida improved his pass blocking skills and if Joe Williams can handle the speed of an NFL linebacker.

Equally as important, notice which running back finds space and gaps on outside zone runs. As you know, zone runs do not have a designated hole for the back to attack.

With zone runs, backs must quickly read the defensive line's position to the blocks. Ideally, the back wants to hit the hole just outside the tight end's hip, but he may have to adjust vertically or cut back against the grain.

So, if you notice an outside zone run, take a look for the gaps in the line and if the running back read his blocks correctly.

Mike McGlinchey's on the Big Stage

Along with the carousel of guards on Thursday, expect rookie tackle Mike McGlinchey to play the first half of this Thursday's game.

Let's assume he's got a good understanding of some of Shanahan's playbook. Now, it's a matter of execution at the next level. Of course, McGlinchey may not face top talent this Thursday. However, he will meet adversaries who are doing everything possible to make Dallas' 2018 roster.

Don't think for a minute an undrafted free agent or a journeyman linebacker isn't going to come at McGlinchey with the full force and fury of a divisional playoff game. Be sure to watch his hands and feet, and see how he takes on different stunts.

I'd like Shanahan to send as many plays as possible McGlinchey's way, anything from a simple toss right to a complex pass protection or a move-the-pocket play that puts the critical block on McGlinchey's shoulders.

Further, I want to see McGlinchey miss a few blocks and then watch him rebound over the next series of plays. Early failure is key to professional development.

Sure, it's the first preseason game, but these games provide an ideal time to focus on different position groups rather than watching the game as a whole. Welcome back to 49er football!

• Bret Rumbeck
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  Bret Rumbeck
  Bret Rumbeck has been writing about the 49ers since 2017 for 49ers Webzone and 49ers Hub. He is a Turlock, CA native, and has worked for two members of the US House of Representatives and one US Senator. When not breaking down game film, Bret spends his time seeking out various forms of heavy metal. Feel free to follow him or direct inquiries to @brumbeck.
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