On Sunday, only one running back had at least 100 yards rushing in a game: Andre Ellington of the Cardinals. Last night, Zac Stacy of the Rams joined him, before leaving the game with an ankle injury. Two rookie backs, playing in the NFC West, who were drafted in the late rounds and were not starters when the season began, were the only two that could top the century mark. There were only two 100 yard rushers the previous week as well: Chris Ivory and Ryan Mathews. Ryan Mathews- yes, that much maligned Ryan Mathews - has two of the last five 100 yard rushing games by a running back in the NFL, and his team was off this week.
If it seems like the running backs are not getting the huge rushing days they have in the past, it’s because it is true. So far this year, a running back has rushed for 100 yards thirty times. Only one running back, LeSean McCoy of Philadelphia, has more 100 yard rushing games than Oakland quarterback Terrelle Pryor (who has two such games after Sunday’s big run). For comparison’s sake, here are the number of 100 yard rushing games by running backs through the first eight weeks, going back the last ten years: 53, 59, 55, 48, 54, 60, 73, 58.
We have been moving toward more committee situations and limited workloads in recent years, and the passing attacks have continued to expand. The drop in 2013, though, is still precipitous. It’s almost half as much as the average from the previous decade (58.6 such games by week 8 on average).
Let’s take a broader view. We have reliable game to game data going back to 1960 on Pro Football Reference. Here is a chart showing the number of 100 yard games by a running back in the first eight weeks of a season, for every year since 1960.
There had been mostly steady increase in the number of 100 yard games over time. One reason is the number of games, of course. There were 21 teams in 1960, between the AFL and NFL (and both leagues are included in those numbers from the ’60′s). By 1970, that had climbed to 26 teams when the leagues merged, and it has been at 32 teams since 2002.
Only two other periods come in as low as this season.In the 1960′s, both the running back and fullback split carries and were used in the passing game while on the field at the same time. To show how the backs were being used then, a back had at least 80 receiving yards in a game 231 times in a season in the sixties. Over the last decade, that number was 122, despite the fact that there are more teams and more games.
The other period was in the early nineties, when the number of 100 yard games took a steep dip in 1990, but rebounded. Gradually, the league moved to a “workhorse back” model, which became especially prominent in the mid-nineties into the middle of the last decade.
The 100 yard rushing game may not be going extinct, because one long run can get you there, and there will be a handful of backs getting a lot of carries. It is, however, seeing its natural range restricted and is on the Endangered Species Watch List. If you look at just rushing yards per game, 2013 is the third lowest average in league history at 107.3 rushing yards per game for the league. However, when you account for rushing yards from other sources (quarterbacks, receivers), it becomes the lowest for running backs ever, at 86.2 rushing yards by running backs.
Rushing attempts are also at their lowest point ever, 26.6 per game. 3.3 of those are coming from quarterbacks. A decade ago, quarterbacks accounted for 2.7 of the 28.3 rush attempts per game.
The other factor, of course, is the number of yards gained when running backs do run. The league average this year is 4.0. The last time it was that low was in 2005, and the last time it dropped below 4.0 was in 1999. The previous two seasons had seen the two highest league-wide yards per carry marks in league history, at 4.3 yards per carry. That has come crashing back. That number is buoyed by the quarterbacks running, also. Among just running backs, the average so far this year is 3.9 yards a carry.
The drop off has been dramatic (and noticeable) in 2013. The number of 100 yard rushers has fallen off. The underlying usage of running backs has changed more gradually over the last eight years. The only way that it rebounds is if the backs start making more big plays and getting long touchdowns, and the yards per carry figures climb back toward the recent numbers of the past five years. I do not see the league reverting to a time when running backs routinely got 30 carries in a game and embracing the workhorse model soon.