Last Monday night felt like everything was finally right and good with the world. As the sun dropped into the Pacific, the nation watched the San Francisco 49ers dismember the cursed Cleveland Browns.

The 49ers' offense could make up running plays in the huddle and gain five or six yards, while the defense spent the evening making quarterback Baker Mayfield look like a second-string junior varsity player.

Then, the next afternoon, the anvils began to fall from the sky. Not only did fullback Kyle Juszczyk sustain an MCL sprain, but the team also announced second-year tackle Mike McGlinchey would undergo arthroscopic surgery on his right knee.

Woe to you, oh Shanahan and Faithful, for the devil sends the injuries with wrath.

On Sunday, the 49ers will have their offensive line bookended by two men with a combined 183 regular-season snaps.

Rookie tackle Justin Skule has played well enough during his first two starts. He hasn't allowed a sack, though he has drawn three penalties.

Journeyman tackle Daniel Brunskill has played in eight regular-season snaps during his career, all with the 49ers this season.

Below is a short film breakdown from the Week 5 win against Cleveland, looking at the tackle position and the variety of runs and protections in head coach Kyle Shanahan's offense.

1st Quarter: 1st and 10 at the 50 (9:32)



'Scat' protection has been around since the late Bill Walsh's 1982 playbook. Back then, Walsh listed it as five-man protection that gave at least one back and the tight end a free release. The offensive line did have help in the backfield.

Shanahan uses 'Scat' protection like head coach Jon Gruden did with the 1998 Oakland Raiders. It's still an empty, five-man protection sliding the line away from the call. Four linemen will block down one way, strong or weak, with the last picking up the edge. However, all eligible receivers have a free release. Keep an eye out for 'scat' calls with a single back.

In the play above, you'll note Skule on an island while his teammates were shifting to their right. Shanahan had no fear placing Skule in one-on-one situations against defensive end Miles Garrett.



Keep in mind that shifting the line in Brunskill's direction, as it might in a 300 Scat call, doesn't help him. He'll still be taking on defenders alone, without any backup from a running back or a guard.

2nd Quarter: 1st and 10 at the CLE 19 (2:00)



The best part about this play wasn't running back Coleman's touchdown - it was the simplicity.

I should note that I might be off in my terminology on the above play, but the general idea is there.

Taxi is a single back play that attacks the outside of the line of scrimmage. The play side guard and tackle pull to their left (or right). The play side tackle must get depth and clear the lane for the back.

The inside blocker takes the end man on the line of scrimmage, while the next will take the first 2nd level defender inside and off the line of scrimmage.

Truck is a similar call in Shanahan's playbook, but you'll see this with a trips set on one side of the line of scrimmage.

I am guessing the play above is a variation of Taxi, with the guard and center pulling, and the tight end and tackle securing the edge.



I like Taxi and Truck calls for Brunskill for two reasons.

First, often placing a lineman in open space limits the number of errors he can make. Even a tackle with limited experience, like Brunskill, is going to win battles against defensive backs. Sometimes the best block is chasing off pesky linebackers or escorting the back downfield.

Second, if Shanahan uses the modified play above, Brunskill's only job is a down block. I do not doubt that Brunskill has made thousands of down blocks, going as far back as junior high school.

3rd Quarter: 1st and 10 at the SF 10 (14:59)



Like 'Scat' protection, 'Jet' is six-man protection that slides the offensive line in one direction, leaving the tackle and back to pick up the other side of the line of scrimmage.

'Jet' protection takes a lot of communication between the line and the backs. The center often blocks the first inline defender in the gap or across his face. The frontside guard may make 'gap' calls to the back, who is already making a double read from the inside and looking out.

In a two-back set, one back has a free release, while the other stays in to block.



As you can see above, Skule and Juszczyk are working together to protect the weak side, while the remaining offensive linemen shifted to the strong side.

Brunskill makes me nervous for a variety of reasons, but mostly the number of reads and calls he has to make this afternoon. He also cannot benefit from Juszczyk's experience to clean up any overpowering defenders who leak through the edge gaps.

3rd Quarter: 3rd and 6 at the SF 14 (13:57)



There are protections Shanahan uses to help his tackles, though I do not notice them often.

Early in the second half, Shanahan called a (3)24-25 Chip on a pass play that gained 16-yards.

'Chip' is man protection, with the offensive line responsible for the four down linemen and the Mike linebacker. The strong side back is responsible for the outside linebacker, reading the Sam to the strong safety or cornerback. The weak side back has a similar read, looking at the Will to the free safety or defensive back.



In this play, running back Raheem Mostert provided McGlinchey with an assist before heading into the play. Mostert did not have a defender to pick up.

Juszczyk gave help to Skule but kept his eyes on the Sam. He left Skule on his own a moment later to pick up the blitzing linebacker.

The 49ers find themselves in this situation because the executives and Shanahan failed to address offensive line depth in the offseason. Indeed, league depth at backup tackle is an inch deep at best. However, that's no excuse to have someone like Brunskill in the starting line-up today.

Brunskill will not have much help today, so I am hopeful Shanahan installed a passing offense that is quick-hitting and does not ask Brunskill to hold his block for more than a few seconds.

Images courtesy of NFL.com.
  • Bret Rumbeck
  • Written by:
    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.