49ers offensive line depth impresses against Rams' fierce pass rush

Over the past several seasons, the 49ers have managed to remain one of the healthiest teams in football. In 2012, despite some notable injuries to role players such as Mario Manningham and Kendall Hunter, they managed to avoid significant injury to any key player for an extended period of time. In fact, they finished the season as the healthiest team in the league by a wide margin.

In 2013, the 49ers have not been so fortunate. That dirty r-word, regression, has made its way to the Bay Area with a vengeance, claiming seemingly another important piece every week. The latest player to find his name on the injury report is left tackle Joe Staley, who made it a mere six snaps this past week before leaving with a knee injury. Thankfully, it does not appear as if Staley will miss a large chunk of time, but the 49ers will be without their top offensive lineman this week against the Seahawks.

It goes without saying that losing a player of Staley's caliber is never a good thing. However, his early departure means we got a good look at the offensive line as it will be constructed this week against the Seahawks while facing a quality opponent. The Rams' defensive line has been a force all season long, ranking second in Football Outsiders' Adjusted Sack Rate and sixth in Adjusted Line Yards (which attempts to isolate the defensive line's impact on run defense). Defensive end Robert Quinn, the man that Staley was going to be matched up with for the majority of the game, sets the pace for a unit that is responsible for 34 of the Rams' 37 sacks. Already down starting left guard Mike Iupati headed into the contest, how did the 49ers offensive line hold up following the loss of its best player?

Colin Kaepernick was sacked four times, but judging the offensive line's performance by that number alone would be a mistake. As James noted yesterday, all four of those sacks came in the first quarter-and-a-half, as the reshuffled unit was still getting settled in. According to Pro Football Focus, Kaepernick was pressured on 32.4-percent of drop backs against the Rams, just slightly below his season average of 34.1-percent. All things considered, it was quite the impressive performance by the men in the trenches.

Without question, Alex Boone faced the most difficult challenge in Staley's absence. Not only did he move from guard to tackle, but also from the right to the left side. Players spend entire off-seasons working on that type of transition and it doesn't always go well. Boone does have experience playing each of the tackle positions, but to make that switch mid-game is just asking for disaster. It's a completely different mindset and it's a testament to how good of a player Boone has become that he was able to make that switch with Kaepernick living to tell about it.

Early on, the 49ers did a variety of things to help him out. There were more three-step drops and quick passes. There was the occasional back or tight end chipping off the edge. There were a few play action rollouts in the opposite direction. Protections were sliding his direction to provide additional help to the inside. Now, I obviously do not know if these were things that were already in the game plan to try and neutralize the Rams' pass rush or if adjustments were made following Staley's injury to assist Boone. Whatever the cause, they certainly helped.

1st Quarter, 4:53 remaining, 1st and 10 at the SF40

Let's start with a play from the 49ers' second drive of the game. They come out in a balanced single back formation with their 12 personnel (1 RB, 2 TE, 2 WR) and the Rams match with their base 4-3. The Rams blitz linebackers James Laurinaitis and Alec Ogletree, bringing six total on the play. Now, Kaepernick is going to look to attack down the field, but this is actually a quick developing play.

With Frank Gore and Vernon Davis staying in to block, the 49ers have a seven man protection to pick up the blitz. Let's focus on Boone, who's responsible for blocking Ogletree off the edge. With Ogletree in such a wide alignment, it's important that Boone is able to get a good kick so that he doesn't get beat with the speed rush to the outside, but he also doesn't want to be too aggressive in closing that distance and end up overcommitting or lunging towards Ogletree.

As you can see in the first frame, Boone is in great position. He's got a wide, balanced base, he isn't leaning towards Ogletree and his hands are up, ready to punch and not hanging down around his waist. In the second frame, you see Boone has jarred Ogletree back with his initial punch and by this time Kaepernick has hit the back step of his drop and ready to throw. Before Ogletree can recover, the ball is out.

The offensive line did a great job across the board in picking up the blitz, giving Kaepernick a clean pocket to deliver the ball from.

Things were not all smooth sailing, though. There were certainly moments where Boone didn't look completely comfortable with all that space on the outside. As good as the overall performance was, there was ultimately a reason why the 49ers decided to move Boone to the inside to begin with. He's nowhere near the athlete that Staley is and there were times in which it showed.

The player who struggled the most in pass protection, however, was Adam Snyder. Getting his second start at left guard in place of the injured Iupati, Snyder's biggest issues seem to come in the form of missed assignments or miscommunication rather than being outmatched physically. That was the case on the second Rams' sack of the day.

1st Quarter, 3:59 remaining, 1st and 10 from the SF35

The 49ers line up in an Offset I Pistol formation with Vernon flexed out to the right side of the offensive line, the Rams again matching with their base 4-3. Similar to the last play, the Rams are bringing the house, this time sending their entire front seven on the blitz. With both backs staying in to protect, the 49ers again have a seven man protection and should be in good position to pick-up the blitz as long as they execute.

Moments after the snap, you can see the 49ers have slid their protection to the left – note how RG Joe Looney begins the play to the right of the hash marks and is now directly on them – with both backs stepping up to account for the blitzing linebackers. But take a look at Snyder. You can see that his head is looking to the outside and only his inside hand is engaging the defensive tackle, Michael Brockers. Go back and look at the pre-snap image again. Brockers, aligned on Snyder's outside shoulder in the three-technique, and Quinn, aligned wide to the left, are the only players outside of Snyder. With Quinn very clearly being Boone's responsibility, there should be no reason that Snyder is looking to anyone outside of him other than Brockers. If anything, he would want to keep an eye to his inside for a linebacker blitzing through the left A-gap, but again, the 49ers are sliding the protection to the left so he would have help from center Jonathan Goodwin if that were to happen.

From there, it only gets worse. For some reason, Snyder seems fascinated with the Boone-Quinn battle on the outside and actually ends up with his back completely turned to Brockers. Despite the rest of the protection holding up nicely, Brockers now has a clear path to Kaepernick without having done much of anything. Kaepernick, already looking that direction to begin the play, sees all of this developing in front of him and looks to escape. But with Snyder providing no resistance, Brockers is able wrangle up our QB before he can get out of the pocket.

Had Snyder been able to keep Brockers at bay even briefly, Kaepernick likely would've had enough time to find Vernon breaking open over the middle of the field. These are the types of issues that seem to plague Snyder. Continuity is one of the most important aspects to effective offensive line play. Any time that you're shuffling parts around up front, miscommunication is going to be a concern. I'm confident that Snyder can hold is own physically on the interior, but these types of breakdowns are going to consistently lead to negative plays.

By the third quarter, Boone and the rest of the offensive line had settled in and looked more comfortable.

3rd Quarter, 1:15 remaining, 3rd and 7 from the SF20

Late in the third quarter, the 49ers are faced with an obvious passing situation and bring out their 11 personnel aligned in a trips right formation. The Rams match with their nickel package and their defensive line spread. The 49ers end up using perhaps the most common pass protection that you'll see, a combo protection. Without getting too in-depth, there are two basic types of protection schemes: man and area. These are exactly what you would think that they are (I swear, if football coaches were responsible for naming everything, breakfast would consist of washing down some "pig ass" with a little "boob juice."). In man schemes, each player in the protection is responsible for a specific defender while in area schemes, players are responsible for whichever defender comes into their assigned area. As you might have guessed, combo protection combines these two schemes.

On the left side of the line, Boone and Snyder are "manned up" against Quinn and Eugene Sims, respectively. On the right, Goodwin, Looney and Davis are going to slide to the right to handle William Hayes and Chris Long, plus any blitzing linebacker.

About a second after the snap, tackles Boone and Davis are near mirror images of each other. Davis's hands are a little low, but both players are in good position and ultimately are able to push the defensive ends up the field and out of the play. Snyder gets knocked back a bit initially by Eugene Sims, but his wide base allows him to recover nicely and render Sims is a non-factor. Goodwin and Looney handle their business against William Hayes and the result is another clean pocket for Kaepernick, who has time to pump fake and drop a dime to Michael Crabtree over the top on the double move.

Most of our time has been spent focusing on the positions vacated by our two best offensive lineman on the left side, but I wanted to briefly touch on the guys to the right as well. Joe Looney was thrust into action following the Staley injury, filling in for Boone at right guard. Perhaps the best thing that I can say about Looney's performance against the Rams was that while I was watching film, I barely noticed him. He didn't have any spectacular plays, but at the same time didn't have any glaring mistakes. He was probably a bit better in pass protection than he was in the run game, but it was a solid effort across the board. That's about as much as you can ask for a player in his position, without any game experience at the NFL level.

If you've spent any time listening to me this season on the Better Rivals podcast, you know that I've been critical of the offensive line throughout the season. Anthony Davis has been perhaps the biggest disappointment. After taking a big leap forward last season and looking like one of the best tackles in football, he seems to have given a little of that progress back this season. With that said, he's now put together his best two game stretch of the season against two formidable pass rushes. He handled Chris Long for the better portion of last week's game and limited him to just a few hurries. Long doesn't have the gaudy sack numbers Quinn has from the other side, but is still a very effective pass rusher.

The 49ers' makeshift offensive line has another tough challenge waiting for them this week with the Seahawks coming to town. They will no doubt benefit from a full week of practice reps, but the cohesion that's so essential to offensive line play doesn't come overnight. Based on their performance against the Rams, I'm hopeful that they can put together another solid effort against the Seahawks. I do think that it's important that the coaching staff carries forward many of the same elements that helped make this outing a success. More three-step drops, more attempts to move the pocket – anything that helps to lessen the burden on the offensive line. If they can do that, we just might be alright.