Identifying fluke RB production

In advance of NFL training camps, we asked Christopher Harris to write an overview of film-watching. He and Field Yates recorded a Fantasy Underground podcast on the topic, and we think it bears elaboration here. Chris and Field are at the vanguard of advocating film-watching as an essential tool of fantasy evaluation, and in this series of articles, Chris will offer an overview of what he looks for on film.

Part 2 of 5: How to tell when great RB box-score production is a lie

It'll happen a dozen times in 2014: An unowned running back will have a big statistical day, and the fantasy waiver-wire rush will be on. But how do you know when to bite?

Every RB in the NFL is a great athlete, which means they'll produce given the right circumstances. But those "right circumstances" often don't recur. That's why you should look beyond the box score, at film.

Here's what I look for when I worry a breakout player might be a fluke:

1. RBs who stop in the hole: If you're looking for one habit that signals a rusher might not be for real, it's a repeated tendency to jump-stop as he approaches the line. Not every run on which a running back stops is his fault -- sometimes his blocking is truly bad -- and not every such run results in failure. But when a surprise weekly star does this a lot, I'll usually tell you not to add him.

Did Barry Sanders often do it? Indeed. But he could literally make people miss beginning at a standstill. That's rare. For lesser RBs (read: all of them), this is an indicator of hesitancy and perhaps poor vision. Decisiveness is a runner's friend; mediocrity begins by stopping in the hole.

Take the 2013 St. Louis Rams backfield. Daryl Richardson began as the starter, and he had 176 total yards in his first two games, but I didn't love what I saw. If there wasn't an obvious running lane, Richardson's first move was to do a two-foot mini-jump-cut, and look around.

When Zac Stacy took the job, I was ready to be just as skeptical, but Stacy doesn't make this move. He usually fires hard to line, cuts once when he needs to, and accepts contact. That's the primary reason he became a favorite of the Fantasy Underground podcast so early on.

2. RBs who are tackled too easily: I asked Field the biggest thing he looks for on a RB's tape, and he said, "How easily he goes down." I like it. When all players are great athletes, sometimes "want to" is the key differentiator. It's fashionable to say that Chris Johnson gave up on many runs in '13, but you know what? It's also true.

I don't know what happened to Ray Rice last year, but on tape it was noticeable: Defenders ran him down from behind and especially from the side. And when Brandon Jacobs stirred the echoes in Week 6 to the tune of 106 rush yards and two TDs, all I could see was either wide-open spaces (the game was against a historically bad Chicago Bears run defense) or a single man clobbering Jacobs' legs and hammering him down.

3. Watch out for big plays anyone could've made: When a big run happens because the RB goes untouched for 30-some-odd yards, it's not a great indicator of future success.

My 2013 whipping boy in this regard was Bilal Powell. Powell torched the Buffalo Bills in Week 3 for 149 rushing yards, and some folks were upset that I didn't believe in him. But I watched the tape.

Powell's three biggest runs that day came on plays where he wasn't touched until he was more than 10 yards downfield. Given that, like Daryl Richardson, Powell also tended to be an inveterate two-foot hop-stepper at the line, the red flag was up.

4. RBs who take a long time to get to top speed: Some of the NFL's bigger backs are speedy when they finally hit their stride. Watch Rashad Jennings burst for an 80-yard TD in Week 11 last year, and you'll see him leaving defensive backs in his wake. But he had so much room to accelerate!

How do you know you're seeing a man with "acceleration problems"? One part of the answer is obvious: when defenders can stay with him as he breaks to the second level. But a subtler sign can occur earlier in a run. When Matt Asiata took over as the Minnesota Vikings' starter in two of the season's final three contests, he missed closing holes in his first few strides, as he just couldn't get going fast enough to reach his creases. The exact opposite is true of Arian Foster, who's roughly the same size as the burly Asiata. On tape, Foster looks like he's gliding near the line, until he sees an opening. Then, boom! Suddenly he's at top speed after a single cut. You rarely see Foster let a crease go unused.

Coming next: How to tell if size/speed WR freaks will be great