At first glance, the matchup between San Francisco’s rushing offense and Baltimore’s run defense looks to be one of the more even match-ups of Super Bowl XLVII.
However, a closer look at the statistics shows the 49ers to have a significant advantage in this area of the game.
In the regular season, both units were efficient, as San Francisco’s running game was third in the NFL in yards per carry (5.1), while Baltimore’s run defense tied for seventh best in yards allowed per carry (4.0).
This success continued into the playoffs. After a poor game against the run in the wildcard round against Indianapolis (allowing over five yards per attempt), the Ravens shut down the Denver and New England running games, holding both teams to under four yards per attempt.
San Francisco, meanwhile gained 7.5 and 5.1 yards per carry in their playoff games against Green Bay and Atlanta respectively.
Stopping our analysis here, we could conclude both units are strong and that predicting who will have the edge in the Super Bowl is a tossup.
Unfortunately for Baltimore, there is more to gauging a running game’s success than yards per carry stats. A statistic that is even more telling is success rate, essentially the percentage of plays that yield positive expected points.
In many ways, SR is more valuable as a predictive tool. As Brian Burke of Advanced NFL Stats notes, “[yards per carry] is too susceptible to a handful of relatively rare break-away runs and wrongly penalizes successful plays in short yardage situations.”
Burke adds that running success rate correlates with winning much more than “simple running efficiency.” It also correlates with itself at a slightly greater rate than YPC does, meaning it is more consistent. The combination of these factors leads to the conclusion that success rate is a better predictive stat than yards per carry.
So what does this mean for the Super Bowl? In short, San Francisco has a greater advantage against the Ravens run defense than yards per carry totals indicate.
The 49ers, led by dual threat quarterback Colin Kaepernick and tailback Frank Gore, have the league’s best success rate on the ground, according to ANS.
Conversely, Baltimore’s rush defense is tied for 22nd in the NFL in success rate (both team SR figures incorporate both the regular season and playoffs).
Based on the disparity between its success rate and yards allowed per carry, we can imply that while Baltimore has not given up many huge runs, it consistently allows significant gains and may also be poor in key situations.
Numbers from Football Outsiders support this conclusion. According to FO, Baltimore is 11th best in second level yards (5-10 yards from the line of scrimmage) and third best in open field yards (beyond ten yards of the line of scrimmage), meaning they have in fact limited big plays on the ground.
Up front, though, the Ravens are getting consistently beat, ranking 26th in adjusted line yards, 29th in power situations, and dead last in stops for no gain or a loss (via FO). Thus, despite containing long runs, teams are able to reliably to gain yards on the ground against Baltimore
As for their success in critical situations, the team fares no better. The Ravens rank 28th in the league against the run on 3rd and 4th down, and are 24th in red zone rush defense, according to FO’s premium stats (subscription required).
These factors explain the apparent discrepancy between Baltimore’s yards allowed per carry total and success rate. Given the latter’s consistency and stronger correlation with winning, we should put more stock in success rate and conclude the Ravens run defense is comparatively weak.
Despite the attention Ray Lewis has received upon his return, his play has hardly helped against the run (or the pass, for that matter). His playoff run stop percentage is a weak 6.5%, tied for 10th among 16 qualifying inside linebackers this postseason, according to Pro Football Focus (subscription required).
Among the Ravens starting front seven, only Terrell Suggs ranks in the top 16 at his position in run stop percentage (Suggs is 14th among 3-4 outside linebackers) (via PFF).
On the other side of the coin, San Francisco is strong in a number of areas where Baltimore is weak.
The 49ers are eighth in the NFL in red zone rushing, according to FO’s premium stats (subscription required).
San Francisco is also first in adjusted line yards, 12th in power situations, and has been tackled for a loss or no gain the seventh least times this season, according to FO.
This is a testament to San Francisco’s offensive line, which is arguably the best run blocking unit in football.
Guards Mike Iupati and Alex Boone are the second and third highest ranked guards in terms of run blocking, and tackles Joe Staley and Anthony Davis are the NFL’s best two run blocking tackles, according to Pro Football Focus (subscription required). Also, center Jonathan Goodwin is hardly a weak link, ranking eighth at his position in run blocking grade (via PFF).
As mentioned, the one area where Baltimore has been successful against the run is containing big gains. Unfortunately, this is another area the 49ers are strong, ranking first in the league in second level yards and 14th in terms of gains beyond 10 yards of the line of scrimmage (via FO).
A big reason for San Francisco’s success in this regard is Gore’s big play ability. The running back is in a tie for the sixth most rushes of 15 or more yards this season, with 16 such rushes, according to PFF (subscription required).
Including the playoffs, Gore has a success rate of 46% this season (sixth best among running backs with at least 100 carries), and has gained 4.7 yards per carry (via ANS).
In addition to Gore, San Francisco has rookie LaMichael James at its disposal in the backfield. After a quiet regular season, James has burst onto the scene in the playoffs and is another big play threat. In the postseason, he has gained 6.9 yards per carry on eight attempts, and has had a success rate of 60% or greater in both playoff games (via ANS).
Finally, it would be wrong to discuss San Francisco’s running game without also speaking of Kaeprnick. According to Scott Kacsmar, though the majority of Kaepernick’s runs have actually been off of scrambles on passing plays, he has been incredibly effective on designed runs.
On all designed runs, according to Kacsmar’s numbers, Kaepernick has gained 9.31 yards per rush. One zone read options, which amounted to 20 of his 35 designed running plays, he has gained almost 11 yards per carry.
All this considered, expect San Francisco to have a distinct advantage when running the ball this Sunday.