Considering potential consistency of 49ers running backs in 2015

A couple weeks ago, Chase Stuart wrote a very interesting article looking at the top running backs and their yards per carry (YPC) for 2014. Specifically, he looked at how many carries you’d have to take away from a back in order to make him average.

If anything, this kind of analysis just speaks to a running back’s consistency. Averages are strongly affected by outliers. If you have just a few big runs on your stat sheet it really makes your YPC look better than it is.

In Stuart’s analysis, Gore would only have to lose one carry to make his YPC number average. That makes sense. Gore isn’t going to break a ton of big runs, but 49ers fans loved his ability to grind out 2–4 yards seemingly every time he touched the ball. How do the other 49ers RBs stack up to Frank Gore, the paragon of consistency?

Carlos Hyde

Hyde wasn’t a part of Stuart’s analysis because at just 83 carries, he did not meet the minimum carry requirement (100). As a matter of fact, not one back on the 49ers roster carried the ball enough times in 2014 to qualify, but that won’t stop us.

Let’s start with the bad. Hyde’s 4.01 YPC number was actually lower than the league average of 4.14. Ordering Hyde’s carries in descending order reveals one outlier - a 28 yard run against The Seahawks in December. Removing that run takes Hyde’s YPC down to 3.72 YPC. Hyde didn’t have another run beyond 15 yards all year.

Looking at his carries, distributed by yards gained, we see that Hyde most frequently gained 3 or 4 yards. This seems right on par with the per-carry number we get after we remove the outlier.

Gore, on the other hand, most frequently gained 2 or 3 yards, a little behind Carlos Hyde. Gore gained 3 or 4 yards on 22.7 percent of his carries, while Hyde gained 3 or 4 yards on 25.3 percent of his carries.

My guess is that this has more to do with Hyde’s violent running style. When he had just 48 carries under his belt, Hyde gained 5 or more yards after contact on 10 of them. That kind of yards after contact turns a 2-yard gain into 7 yards, and begins to shed light on why Hyde’s distribution bell curve is wider than the next back in our mini-study.

If we dig a little deeper and look at Football Outsiders success rate metric, Frank Gore was successful on his runs 50 percent of the time. This metric is really helpful because it factors in down and distance. a 10 yard run on 3rd and 22 looks good on a stat sheet but is nearly useless in a game.

Carlos Hyde's success rate in 2014 was 46 percent, about league average. If Hyde had enough carries to qualify, he would have been tied for 15th in the NFL. Frank Gore's 50 percent success rate placed him 11th in the NFL in 2014.

Kendall Hunter

To evaluate Kendall Hunter, we’ll have to look at his 2013 numbers, since he sat out most of 2014 due to injury. The methodology here will be a little wonky, as we’re going to compare Hunter’s 2013 numbers to the 2014 average YPC, but for our little thought experiment it should be fine.

Hunter averaged 4.59 YPC in 2013, which seems impressive. However, removing Hunter’s top run, a 45-yard jaunt against the Falcons during the last game at The Stick, brings his average down to a little over 4 YPC. In general, the more runs you have to remove to make a running back’s YPC average the better and this just goes to show how much a few runs can really skew a back’s YPC.

His run distribution graph shows us that, in 2013, Hunter most frequently gained just 2 yards. His distribution curve is compressed to the left (which is not good), and he gained 3 or 4 yards on just 14 percent of his carries. That’s an 11 percent drop when compared to Carlos Hyde.

However, Hunter gained 20 or more yards four times on just 78 carries in 2013. In 2014, Gore gained 20 yards or more 4 times as well, but he needed 255 carries to match Hunter’s explosive runs.

Hunter did not grade out well when it comes to success rate. In 2013 Hunter’s success rate was just 36 percent, putting him 44th out of 47 backs that had enough qualifying runs.

Reggie Bush

Reggie Bush has a similar amount of carries as Hunter from 2013 and Hyde from 2014. All three backs had between 76 and 83 carries. In other words, the sample size is equally small for everyone but Frank Gore.

Bush’s YPC number (3.91) is the lowest of everyone we’re looking at, even before removing his outlier run. Removing Bush’s 26-yard run against the Packer’s brings his YPC number to 3.61.

His run distribution graph remains relatively large all the way though 6 yards, meaning that he is able to consistently get between 0 and 6 yards. And with a 2013 success rate of 47 percent, the numbers suggest that Bush might be a suitable replacement for Gore, presuming he can stay healthy.

Looking closely at the numbers, though, should give 49ers fans pause. Bush was able to get 3 or 4 yards on just 19.7 percent of his carries and he gained 0–2 yards on 36.8 percent of his carries. In other words, Reggie Bush is just as boom or bust as Kendall Hunter, but the boom is 15 yards, and the bust is 0 yards. If anything this tells me Bush is consistently inconsistent.

Conclusions

So far, the numbers tell us that there’s not a back on the roster that is as consistent as Frank Gore.

The back with the most promise is Carlos Hyde. He frequently gets 3–5 yards and has another mini spike at 9–15 yards. His frequency of yards gained graph is the one that most resembles Frank Gore’s, even if he isn’t as consistently successful. The difference between a 46 percent success rate and a 50 percent success rate is probably the most positive note for Hyde. Another positive for Hyde? Three of his top–10 runs based on yardage came against the Seattle Seahawks.

Kendall Hunter seems to add an element of speed and explosion the 49ers sorely need. If a player is going to break a long run on an outside sweep, that player will likely be Hunter. His numbers tell the story of a boom/bust player when it comes to runs and in 2015, the 49ers are going to need all the boom they can get.

As for Reggie Bush? Well, let’s just say that the numbers bear out what David Neumann concluded in mid-March: he likely doesn’t make the 49ers offense better.

Losing Frank Gore, who at this point is on the cusp of a Hall of Fame career, is a loss for any team. But the 49ers are in a good position to replace Gore’s consistency with their current crop of backs. Hyde should be the primary back, with Hunter providing a change of pace and Bush rounding out the backfield as a third down back.