The San Francisco 49ers made a big splash this past offseason when they signed Jerick McKinnon to a four-year contract worth $30 million, with $11.7 million fully guaranteed at signing. There was competition for McKinnon, but either way, that is a lot of money for a guy who had not held down a starting job previously.
When McKinnon suffered a torn ACL before the regular season even started, there were plenty of concerns. Head coach Kyle Shanahan acknowledged the team had to adjust their game-plan for the season with their top running back sidelined. They signed Alfred Morris to compete with Matt Breida, but there were plenty of questions as Week 1 approached.
Six weeks later, it’s safe to say we’ve seen some incredible answers. Matt Breida is tied for seventh in the NFL with 430 rushing yards, and leads the league averaging 6.8 yards per carry. Alfred Morris provides some punch as a complement, but we saw Raheem Mostert provide an unexpected boost in Week 6. Breida led the team with 14 rushing attempts, but Mostert led the team in yards and average, rushing 12 times for 87 yards. Mostert and Breida combined for 148 yards, averaging 5.69 yards per carry.
The 49ers likely wanted a little more speed in the mix against the Packers, thus the reason Mostert got more work than Morris. Mostert would appear to have earned a bigger role moving forward, but I suspect we’ll still see plenty of Morris.
As great as the numbers are for the 49ers running backs, the offensive line deserves a ton of credit. A look at some of the advanced analytics offer details on what head coach Kyle Shanahan, running backs coach Bobby Turner, and offensive line coach John Benton have done in relatively short order. We’ll have a film breakdown coming on Friday, but in the meantime, Football Outsiders and Pro Football Focus offer us some useful nuggets to add a little context to what we are seeing on the ground.
Football Outsiders ranks the 49ers offense No. 25 overall in efficiency, and No. 11 specifically in rushing. FO offers a look at offensive lines, which helps us try and separate out what the backs are done vs. what the line itself is creating for them. The 49ers line ranks No. 2 in adjusted line yards, behind the Los Angeles Rams. ALY attempts to value the offensive line in the ground game, giving it a certain amount of credit for different runs, adjusted for down, distance, situation, opponent, and shotgun vs. under center handoff.
FO ranks out running backs using their proprietary stats, and it’s no surprise Matt Breida ranks near the top among running backs. He ranks fourth in DYAR and second in DVOA. DYAR gives the value of the performance on plays where this RB carried/caught the ball compared to replacement level, while DVOA represents value, per play, over an average running back in the same game situations. In this case, Breida is dominating both overall and on a per play basis.
They use one other stat called Success Rate, which measures a back’s consistency. Breida ranks 12th in consistency. That coupled with his high DVOA ranking means he is mixing long runs with downs getting stuffed at the line of scrimmage (as opposed to consistently getting enough yards for success but not many long runs). We can see this further emphasized in PFF’s breakaway percentage stat. This stat shows which runners earn the highest percentage of their yardage on designed runs of 15 yards or more. It should surprise nobody that Breida ranks third among all running backs with at least 25 rushing attempts (he has 63).
Breida has benefited from a strong offensive line. Prior to Week 6, he had gained 71 percent of his rushing yards after first contact came 2+ yards after the line of scrimmage. However, the 49ers ground game has taken things to the next level in part because of Breida’s breakaway ability.
The NFL’s NextGen Stats offer up an efficiency stat that further backs this. Their efficiency stat takes the total distance a player travels on rushing plays as a ball carrier. The idea being that a lower efficiency number, the more of a north/south runner a player is. Breida ranks seventh most efficient among 48 running backs with at least 35 rushing attempts. Breida is not trying to string runs out down the line looking for holes. The 49ers offensive line is creating holes up the middle, and Breida is decisive in hitting his holes.
Akash will have a film breakdown of the ground game on Friday, so those who prefer the eyeball test will be able to see with their own eyes what the line and Breida (and Mostert) did against the Green Bay Packers. But to date, the numbers are painting an intriguing picture of a rushing unit.
This week, they face a Los Angeles Rams defense that saw some sizable investments this offseason, but has been a bit inconsistent through six weeks. Football Outsiders ranks them No. 17 overall on defense, with the rush defense an abysmal No. 26. Pro Football Focus ranked their run defense No. 12, based on their grading system. PFF noted the Rams are tied for 11th in explosive runs allowed, but 26th in team run defense stuff percentage.
The 49ers badly need to keep the Rams offense off the field. The defense had its moments against the Packers last week, but Aaron Rodgers still put up some monster numbers. It was still a winnable game, but against that explosive Rams offense, the best defense will be controlling time of possession — and of course, actually punching in touchdowns rather than settling for field goals. But if the 49ers are going to have any prayer of an upset, it will come courtesy of the ground game offering a dominant performance.