49ers vs. Seahawks: An Advanced Statistical Preview

Note: All of the data used in this article, unless otherwise specified, is courtesy of Football Outsiders and their premium DVOA database. DVOA is FO's per-play efficiency metric that compares the result of each play to league average after adjusting for down, distance, game situation and opponent. A positive DVOA is good for the offense, a negative DVOA good for the defense. You can read more about it and the rest of their stats here.

It's Seahawks Week. As Coach Harbaugh said earlier in the week, if this game doesn't fire you up, then what does? Unfortunately, it will not be the NFC West-deciding game that we anticipated it to be prior to the start of the season. That's been decided already. Seattle needs only to win their remaining home games to secure the number one seed and home field advantage in the playoffs. But in an increasingly tight wild card race, for the 49ers it remains an important game that could certainly have an impact on the playoff picture.

On a macro level, the 49ers and Seahawks are very similar teams. Both teams want to run the ball, play great defense, limit mistakes and most importantly, be more physical than the other guys. On a micro level, they go about accomplishing those things in very different ways. San Francisco uses a power running game that features more straight-ahead runs and pulling guards; Seattle is a zone-based running team. San Francisco prefers heavy personnel groupings with multiple backs and tight ends on the field; Seattle typically uses single back formations and are more willing to spread things out. The 49ers run a base 3-4 defense; the Seahawks have their 4-3 under. These differences are part of what makes this match-up so intriguing.

Let's dig a bit further into some of those match-ups and take a look at some of the advanced stats that comprise them.

49ers Offense vs. Seahawks Defense

The Passing Game

In case you haven’t been paying attention, Seattle’s defense is good. Like, really good. The Seahawks have the best defense in the league according to Football Outsiders with a -20.7-percent DVOA. Seattle is responsible for the 49ers’ worst single-game offensive performance this season, as measured by that same metic. Their defense is powered by Richard Sherman, Earl Thomas and the league’s best pass defense. Seattle is pacing the league in pass defense DVOA by a significant margin. Following their dominating effort against the Saints, the Seahawks pass defense DVOA sits at -27.5-percent, nearly 10 percentage points better than the second place Bengals. Only five other teams are even better than -10-percent.

San Francisco’s passing game has been much better by the advanced numbers than you would probably think given how much negative attention it has received over the course the season. They currently rank fifth in pass offense DVOA. If there is one potential area to attack in the passing game, it’s going to be throwing in the direction of corners that aren’t Richard Sherman. Without Brandon Browner and Walter Thurmond, that’s going to mean attacking the likes of Byron Maxwell and Jeremy Lane. Neither guy is all that big of a drop-off from Browner and Thurmond. With Sherman on the other side, they will certainly receive help from Thomas over the top. But against number two receivers this season, Seattle ranks 22nd in DVOA, their worst ranking against any pass target.

The 49ers may find it difficult to get Vernon Davis going this week. Due in large part to the coverage ability of linebacker K.J. Wright and their safeties, Seattle ranks second in DVOA defending tight ends. Against New Orleans, they managed to hold Jimmy Graham to just three receptions for 42 yards on nine targets. In his last three games against Seattle, Vernon has just four receptions for 47 yards. They also rank second in DVOA defending running backs and "other" wide receivers, but we don't throw to those guys anyway, so whatever.

The Running Game

If there's one potential soft spot in Seattle's defense, it's their 11th ranked run defense. This will likely be the 49ers best opportunity to exploit the Seattle defense. It’s been a struggle for Frank Gore and co. lately, as their run offensive DVOA has been in the negative every week since the bye. I’m of the opinion this recent lack of production has been the result of opposing teams making it their sole focus to stop the run more so than any failure on the players’ part. Opposing defenses are stacking the box with 8, 9 and even 10 defenders on some plays and there’s no reason to expect any different from a Seattle team that already likes to drop a safety down into the box regardless of the team they’re facing.

Seattle’s defense is too fast and skilled for teams to find success out on the edges, but they do appear to be vulnerable on runs up the middle. On runs between the guards, the Seahawks rank 26th in Football Outsiders’ Adjusted Line Yards, which is their worst ranking in any run location by a pretty significant margin. Tampa Bay was able to have success with this approach, as they gashed Seattle up the middle to the tune of 7.38 yards per carry on 13 carries. The 49ers have been able to break big plays against Seattle in the past using their Wham and Trap runs, quick hitters that attack directly up the middle. They will need to find a way to do so again this week.

Explosive Plays

Whether or not they come on the ground or through the air, San Francisco has to generate explosive plays to be able to come away with a victory. When the 49ers fail to produce big plays, they’ve been unable to sustain drives. According to Football Outsiders data, the 49ers have gone three-and-out on just over 27-percent of their drives, the sixth worst rate in the league. They’ve still been able to put up points at a solid rate, averaging 1.97 points per drive, good for 13th. Essentially, this means that when drives have been good, they’re really good and San Francisco is putting points on the board. But when drives are bad, they’re really bad and the 49ers are failing to pick-up first downs.

Obviously, there is value in simply sustaining drives, even if they don’t result in points. You’re able to flip field position and force your opponent to travel further to put points on the board. You gain time of possession, giving your defense a breather and keeping the opposing offense off the field. It’s difficult to consistently do this picking up four and five yards all the way down the field. You have to be able generate explosive plays.

Michael Sawyer over at Field Gulls has been charting explosive plays for the Seahawks and their opponents this season and he did so for the 49ers yesterday. Michael defines an explosive play as a run of at least 12 yards and a pass of at least 16 yards. San Francisco is averaging 7.25 explosive plays per game this season. He also charted the number of total drives that included at least one explosive play. I compared those numbers with the 49ers overall drive numbers and the results were staggering.

Excluding kneel down drives, San Francisco has had 139 total drives, scoring 31 touchdowns and 19 field goals for a total of 274 points. According to Michael, the 49ers have had 61 explosive drives, scoring 28 touchdowns and 11 field goals for a total of 229 points. Some basic math tells me that explosive drives have produced 83.5-percent of the 49ers' point total on just 43.8-percent of their drives. That seems like it might be important. We saw what the addition of Michael Crabtree to the lineup has the potential to do on this front when he broke loose in the Rams' secondary for a 60-yard gain. If Vernon ends up in shackles again, the onus will be on Crabtree to produce the big plays in the passing game that we need.

Seattle's defense has done a good job at limiting these explosive plays, giving up an average of 5.58 per game. With two very good defenses and a game that seems destined to be low scoring and tightly contest throughout, the ability to generate these explosive plays on offense could very well be the difference in the game.

49ers Defense vs. Seahawks Offense

The Passing Game

After a rough stretch through the middle of the season, Seattle's passing offense seems to have returned to the level it was at over the second half of 2012 in which it was running amuck over the rest of the league. They now boast the fourth ranked passing offense according to DVOA including games of 112.0-percent and 108.1-percent the last two times they've taken the field. Russell Wilson and his cast of pass targets have been playing at a level more than twice as good as league average. That's not too shabby.

The good thing is the 49ers pass defense has also been playing very well. San Francisco's pass defense DVOA has negative (again, good for the defense) in every week since the bye with three of the four games below -30-percent. Tramaine Brock and Donte Whitner have played particularly well over that stretch.

A key situation in which the 49ers must be better is on first down. They've been lights out in most other situations, but have the 20th ranked defensive DVOA on first down primarily due to a pass defense that ranks 22nd (20.3-percent) in that situation. The Seahawks, on the other hand, have been the fourth best passing offense on first downs. San Francisco will need to be more effective on the opening down to force Seattle into longer down and distances situations, making it more difficult for them to be able to sustain drives.

With nine sacks in the past two weeks, the 49ers' pass rush has found its stride. Aldon Smith, Ahmad Brooks and the rest of the guys up front should have their opportunities on Sunday. While Russell Wilson has only been sacked 30 times this season, which is just below league average, because they pass the ball so infrequently compared to most teams they have an Adjusted Sack Rate of 8.9-percent, ranking 29th. Only the Eagles, Jets and Raiders have been worse throughout the season. Seattle has recently gotten both of their starting tackles, Russell Okung and Breno Giacomini, back from injury. While Okung is a very good player and will help on the blind side, the rest of the offensive line is still mediocre at best and there should certainly be opportunities to get after Wilson.

The Running Game

Much like San Francisco, Seattle is one of the most run heavy teams in the league. And much like San Francisco, their run game has slowed a bit in recent weeks as they've been forced to deal with defenses stacking the box and selling out to stop the run. But at 4.9-percent, they rank eighth in run offense DVOA and are one of only 11 teams that have a positive number in that category. The 49ers haven't had quite the same level of elite run defense they've had over the past several seasons, as they currently rank 13th in run defense DVOA. That's mostly due to a stretch during the middle of the season in which they were dealing with a lot of injuries along the defensive line. With the return of some of those players from injury and guys like Tony Jerod-Eddie playing better, the run defense has solidified in recent weeks. That includes two games below -25-percent DVOA against two top-six run offenses in Washington and Carolina.

Seattle has been most effective running the ball to the left side of their offensive line. Going back to Football Outsiders' Adjusted Line Yards by run direction, the Seahawks rank 10th on runs to the left end and sixth off the left tackle. With 35-percent of their runs headed that direction, they run the ball more frequently to the left than all but Washington and Dallas. San Francisco employs a couple of Smiths that hang out on that side of the line, you may have heard of them.

Explosive Plays

Not going to spend too much time here. If you're interested, check out the previously linked Field Gulls article for the details. The short version is that Seattle has generated about nine explosive plays per game, most of which have come via the passing game. They've only been held below that mark three times this season, one of which was the first match-up against San Francisco.

The Verdict

There's no denying that Seattle has been the better team over the course of the season. However, when you take them out of Century Link they go from being the best team in football to simply being a very good team. The 49ers are capable of beating a very good team at home.

You can say this headed into most games, but it's going to be crucial that San Francisco avoids turnovers as that was a large reason why the first game between these two teams turned so ugly. The 49ers turned the ball over five times that day. Those turnovers led to some fantastic field position for the Seahawks, who had three scoring drives begin inside the 49ers' 30-yard line.

I imagine this game playing out much like the Panthers game; a low-scoring, defensive affair in which neither offense is able to consistently get anything going. In these types of games, the result so often comes down to the outcome of just a handful of plays, amplifying the importance of winning the explosive play and turnover battles. If the 49ers are able to accomplish that, it should be enough to exact revenge on their division rival.