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Advanced statistical review: The running backs

I take a look at how Frank Gore and Kendall Hunter fared against the Jaguars on Sunday.

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Bob Martin-USA TODAY Sports

By and large, the statistics in this post are coming from Pro Football Focus. They have signature stats that are more conventionally comprehensible (like how many QB hurries a lineman gives up). In addition, though, PFF provides weekly "grades" that are overall numbered scores. You can read about their grading process HERE. Positive numbers are good while negative numbers are bad. Anything above +1 is a really good game; anything below -1 is a really bad game. The grade is a composite grade of different smaller grades (like "pass blocking"). I will typically highlight the strengths and/or weaknesses of a particular performance by looking at these composite grades.

Well, that was a blowout. And, by golly, it was bloody fun to watch.

In trouncing the Jaguars 42-10, the 49ers capped off their recent run of great games in a decisive fashion. And, as is usually true when the 49ers win games, a lot of that had to do with an excellent game from Frank Gore. As we will see when we get to his Pro Football Focus grading, there are a few ways to think that Gore had just an okay game. I'll point some numbers out to support this. I don't necessarily disagree with PFF's slightly underwhelming grade. But, Gore did everything the team needed, particularly in setting up the play-action pass.

So, let's take a look at how our top two RBs did this game.

Frank Gore: 0.2 Overall PFF Grade, 19 Rush Attempts, 71 Yards, 3.73 Y/A, 2 TDs, 19T Long Run, 24 Yards after Contact, 1 Fumble, 1 Reception, 6 Yards

So yeah, there are a couple of ugly numbers up there. I get it. The 3.73 yards per rushing attempt is pretty ugly. I won't fight anybody on that. And, this has largely been due to inconsistent attempts, rushing for a long run of 19 yards (and a TD) at times, and getting tackled behind the line at others. The vision is still there, of course, but some of his initial burst has diminished - as has the top-end speed (which he never had much of in the first place). So, this is all reflected in the 0.2 grade PFF has assigned. Gore received a -0.3 in the pass game, a -0.6 in the run game, a 0.1 in pass blocking, and a 1.0 in run blocking for an aggregate score of 0.2. These are lackluster grades, of course, and they represent the inconsistent nature of Gore's game.

First off, in respect to the lackluster grade, Gore did something he rarely does: fumble the Football. This likely does, and should, drag his grade down. But, I don't think we should worry about that too often going forward. He hasn't had major fumble problems. But, what has been a bit disconcerting is his inconsistent running behind the line of scrimmage. Against the Jags, Gore had a great time running behind the LT and both sides of the C. Behind the LT, Gore had 1 run for 9 yards. To the left of C, Gore 6 carries for 24 yards (a 4.0 average) and to the right he had 4 attempts for 32 yards (and average of 8 yards per carry. This all adds up to 10 carries for 56 yards in the A-gaps, but only 9 carries for 15 yards elsewhere.

While some of the blame should go on the o-line, I think we need to recognize the fact that Gore isn't as explosive as he used to be. He is still an elite runner because of his incredible vision and Football instincts: in fact, Football Outsiders ranks Gore 7th in the leagure according to his 92 DYAR ("or Defense-adjusted Yards Above Replacement, which gives the value of the performance on plays where this RB carried/caught the ball compared to replacement level, adjusted for situation and opponent and then translated into yardage"). He is #11 in the league when one ranks him according to his 6.1% DVOA ("this number represents value, per play, over an average running back in the same game situations"). But, this is, believe it or not, a step down for the otherwise indomitable Gore. It's almost tough to imagine, but Gore used to be even better than the superhero we are watching now.

So, yeah, Gore had a better game, I think, than PFF is giving him. He still keeps this offense moving. But, I can understand why he was graded the way he was.

Kendall Hunter: 1.4 Overall PFF Grade, 9 Rush Attempts, 84 Yards, 9.3 Average, 42 Yards after Contact, 41 Yard Long Run

Conversely, Hunter is still a young, up-and-coming back. But, he has been a steller back-up for Gore, and this game demonstrates why. When Gore needed to come out, Hunter stepped in and pulverized a weakened defense. His 1.4 PFF grade is based almost entirely on a 1.3 grade for running the ball. And where was he most effective? Like a true change of pace back should be, where Gore was not. He only run in an A-gap once, for no yardage. But, on the outside, he ran wild. Off the left end, he had one monster run for 41 yards. Off the right end, he had 4 attempts for 36 yards, which is an average of 9 yards per carry.

In what limited carries he has had this year, Hunter has performed quite well. Football Outsiders gives him a respectable 23 DYAR and a nice 6.2% DVOA. That's quite good for a backup RB. While I do expect Gore to continue to be the main back this season, don't sleep on Hunter continuing his strong season.

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