We used expected rushing yards -- the offseason's new advanced metric -- to take a deep dive into running back play on Tuesday. Now, let's look at how it will soon help shape opinions of a position group whose performance has long been difficult to quantify: the offensive line.
Film study can tell us a lot about an offensive line, but that requires devoting countless hours to watching every play (and not just once, but three to four times at a minimum). Pro Football Focus' player grades are a handy resource, but they provide just one frame of reference for evaluating O-line performance. Enter Next Gen Stats' expected rushing yards per carry (xYPC).
Offensive line play is just one factor that determines xYPC, but ranking the top 10 offensive lines from 2019 based on xYPC, as we've done below, gives us an idea of how effective these units were at creating opportunities for running backs on a per-play basis. What will be interesting is the juxtaposition of rushing yards over expectation (RYOE) alongside xYPC, which can tell us a lot about whose rushing struggles were more the fault of the offensive line and whose were more the fault of the team's running backs.
For example, no one in the NFL had a steeper climb in front of him than Le'Veon Bell in 2019. The Jets as a team posted the lowest xYPC in the entire NFL at 3.81, and of the seven worst teams in xYPC in 2019, only one -- Houston -- made the playoffs. And that mark of 3.81 was for all ball-carriers in New York; the xYPC when Bell was given the ball was even lower (3.7). As we know, if you can't run the ball effectively, chances are, you won't win many games. Not that Bell entirely escapes blame -- using xYPC to read between the lines (pun intended), we see that Bell produced an underwhelming RYOE per attempt of -0.41, meaning he was rushing below the expectation set by the team's per-play performance. No one was crowning Bell last season.
Over in Philadelphia, meanwhile, Miles Sanders delighted Eagles fans with his 818 rushing yards on 179 carries (4.6 YPC). Those numbers obviously look better than Bell's (789 rushing yards on 245 carries, with 3.2 yards per carry), but we can also see that Sanders was working with a personal xYPC that was a full yard higher (4.7) than Bell's with the Jets -- and, in fact, Sanders finished with a YPC that was actually below expectation (-0.16 RYOE per attempt).
Other factors, including offensive scheme and situation, can impact xYPC, as mentioned above. Defenders likely keyed on Bell while knowing they wouldn't have to worry too much about someone else beating them. Sanders, as a rookie, was focused on much less (at least early) and ran behind a significantly better offensive line. Even so, we can use xYPC to illuminate how a bad line can make a good running back look horrible, while a good line will help a rookie get out to a fast start.
Before we get started, here again is a glossary of these new acronyms:
- YPC: Yards per carry
- xYPC: Expected yards per carry (the baseline metric for blocking effectiveness)
- ERY: Expected rushing yards (total for the season)
- RYOE: Rushing yards over expectation
- RYOE per attempt: Rushing yards over expectation per attempt
OK, now it's time to highlight the best-performing offensive lines according to xYPC. Be prepared for a few surprises and a few knocks on your favorite running back who might deserve more of the blame for ground struggles than his less-heralded teammates in front of him.
2019 stats: 4.69 xYPC, 1,815 ERY, 125 RYOE, 0.32 RYOE per attempt
This ranking should be expected, seeing as the Ravens led the entire league in rushing in 2019, but their sheer dominance on the ground extends beyond simply leading the league in xYPC (an achievement in its own right). The Ravens ran the ball 387 times, tied with the Cowboys for seventh-most in the NFL, yet they led the NFL in yards per carry as the only team to break 5.0 in the category. Their RYOE per attempt of 0.32 landed them at ninth in that category, suggesting that while their running backs -- by the way, these numbers don't include the efforts of Lamar Jackson, because of position limits -- were incredibly effective on the ground, their offensive line was even better. It was so good and set the bar so high, the ball-carriers didn't manage to lead the league in RYOE because, well, they were expected to do well thanks in part to the superb play of the guys up front. Greg Roman's offense was spectacular in 2019 because of the ground attack and the special play of Jackson, but that offensive line also deserves as much credit. We'll see how it does without retired guard Marshal Yanda in 2020.
2019 stats: 4.62 xYPC, 1,782 ERY, -98 RYOE, -0.25 RYOE per attempt
OK, listen -- I know the Eagles were incredibly banged up last season, and they weren't exactly trotting out three versions of in-his-prime Terrell Owens in their receiving corps, so their running backs were at a bit of a disadvantage. But let's take a moment to heap praise on the Eagles' line, the lone group that remained somewhat intact throughout the season while everyone else took turns in the trainer's room. Philadelphia performed better in xYPC than its NFC East rival Dallas -- logging 4.62 xYPC versus the Cowboys' 4.16 -- it just lacked star ball-carriers to take full advantage (we talked about Sanders above already). The Eagles weren't the only team with a negative RYOE to land in the top 10 in xYPC, either, with half of the group ending up in the red. But they were the only one of those teams with an offensive line (plus two solid tight ends) good enough to help clear space for what should've been over 4.6 yards per carry on average. The loss of guard Brandon Brooks this offseason could be devastating for 2020. Hearing the news of his Achilles injury pained me very much, but the return of Jason Peters in an unfamiliar guard role means the team might be able to weather that storm. Meanwhile, it's time for Andre Dillard to own the left tackle job he was drafted to take. If the Eagles can stay healthy and find a way to replicate what they did up front in 2019, they should win more than the nine games they took home last season.
2019 stats: 4.5 xYPC, 1,246 ERY, 32 RYOE, +0.12 RYOE per attempt
Kliff Kingsbury's first season brought new energy to a Cardinals franchise that seemed to lose some vigor following the (brief) retirement of Bruce Arians in 2017 and one-year tenure of Steve Wilks. Thanks in large part to Kyler Murray, the acquisition of Kenyan Drake and some big changes in personnel up front, the Cardinals managed to find success on the ground a year after struggling mightily. The true praise should be showered on Kingsbury's scheme, though. The numbers back it up: Arizona's offense sent out four-plus wide receivers on 33 percent of snaps in 2019 -- the Cardinals were the only team to do so more than 10 percent of the time -- which led to lighter defensive boxes (less than seven defenders). In fact, more than half (56.7 percent) of Arizona's rushes were into light boxes. It's simply a numbers game at that point; less defenders to block means a higher chance of success for the offensive line. Then Arizona's ball-carriers were able to do the rest of the work, largely reaching and often clearing xYPC. Arizona's change in scheme contributed to the league's highest year-to-year jump in xYPC, from 3.78 in 2018 to 4.5 in 2019 (+0.72). It only translated to two more wins, but it's a great foundation to build upon in the desert.
2019 stats: 4.44 xYPC, 1,394 ERY, -235 RYOE, -0.75 RYOE per attempt
This is our most glaring case of ball-carriers failing to hold up their end of the bargain while working with what appeared to be an effective offensive line. We highlighted this in the intro of the top-10 running backs piece, but now it's really time to explain how badly Devonta Freeman hurt Atlanta's offense in 2019. Freeman was the worst in the entire league (among those with a minimum of 100 rushes) in RYOE per attempt, logging more than a full yard below expectation per carry (-1.18). His RYOE total for 2019 was -218, also worst in the NFL. While Atlanta indirectly acknowledged Freeman's ineffectiveness by cutting him with plenty of time left in his hefty contract, we now have statistical proof to support the case that it wasn't the offensive line's fault, as many fans love to initially blame. The line did well -- in fact, Atlanta was elite when it came to xYPC -- and that was without a key addition, 2019 first-round guard Chris Lindstrom, who only appeared in five games.
There is bad news, though. Freeman's replacement for 2020, Todd Gurley, was also near the bottom of the league in the same categories. His -0.67 RYOE per rush and -150 RYOE on 223 carries helps explain the Rams' struggles last season. We'll see if he can turn it around in Atlanta.
2019 stats: 4.42 xYPC, 1,878 ERY, 167 RYOE, +0.39 RYOE per attempt
I was a bit surprised to see the 49ers weren't rated higher, considering their effectiveness on the ground. Kyle Shanahan's scheme, his use of fullback Kyle Juszczyk and the blocking effectiveness of guys like tight end George Kittle, tackle Joe Staley (enjoy retirement!) and the rest of the bunch created a monster on the ground in 2019. No team rushed for more yards strictly with running backs (2,045) than the 49ers. The 4.42 xYPC puts the Niners in the top five of the league, which is very surprising, considering defenses loaded the box against them (eight-plus defenders) at the highest rate in the NFL (34.4 percent). Their positive RYOE per attempt hammers home what we already knew: The 49ers ran to the Super Bowl with both an effective offensive line and a stable of running backs with excellent vision and burst. That combination was deadly against everyone but the team displaying the Lombardi Trophy in Kansas City.
2019 stats: 4.42 xYPC, 1,462 ERY, 41 RYOE, +0.12 RYOE per attempt
We have our first tie in xYPC, and we've turned to supplemental information to help break it. San Francisco topped New Orleans in yards gained before close (yards gained before a defender closed within 1 yard of the ball-carrier), which illustrates how well linemen are preventing defensive penetration, and in 10-plus-yard run percentage (13.2 percent versus the Saints' 10.9 percent). The first number could've been partially attributed to the difference in total carries, which was nearly 100, but the second clinches the tiebreak, with San Francisco boasting a higher percentage despite having more chances to fail. Now that we've got that out of the way, let's talk about the Saints' offensive line, which shouldn't miss a beat in 2020. New Orleans struck gold with center Erik McCoy, who was a stud as a rookie, and rode the rest of its experienced and stellar offensive line to a top-five mark in xYPC. The positive RYOE total tells us what we already knew about a backfield that included Alvin Kamara -- even after the loss of Mark Ingram. And after cutting Larry Warford and replacing him with the best interior offensive lineman in the draft in Cesar Ruiz, the Saints should keep on winning up front.
2019 stats: 4.37 xYPC, 1,743 ERY, 89 RYOE, +0.22 RYOE per attempt
We can confirm that the Colts' offensive line is also very good. These numbers should jump in 2020, as long as Philip Rivers can play like he has when blessed with adequate offensive line play after working behind a sieve in Los Angeles last season. The fact that Anthony Castonzo bypassed retirement to return helps a ton and keeps the starting five intact for another go-around. The presence of rookie Jonathan Taylor in a backfield that sorely missed Marlon Mack in two key weeks last season should also make this offense a more well-rounded group. As for 2019, the explanation is fairly simple: The Colts, as they have for a couple of years now, are very good up front -- they posted the best mark in rush yardage before close of this group at 0.8 -- and when the rest of the offensive pieces are available and playing up to expectation, they're a good football team. We should expect to see them in this group again next season.
2019 stats: 4.33 xYPC, 1,526 ERY, -146 RYOE, -0.41 RYOE per attempt
I know -- what a stunner! Lions fans will be the first to tell you that if they just had Matthew Stafford healthy for all of 2019, things would've been different, and statistically, that seems to be kind of true. Detroit's O-line helped the team make a major jump in xYPC in 2019, leaping from 3.84 in 2018 to 4.33 -- yet the Lions were one of the league's worst squads after Stafford's season ended in November. With guys like David Blough and Jeff Driskel lining up under center, defenses had little incentive to do anything but prioritize stopping the run. It should come as no surprise, then, that Kerryon Johnson posted a RYOE per attempt of -0.48 and a RYOE total of -54. His teammates clearly didn't fare much better, overshadowing what was an encouraging year-to-year improvement up front. Get Stafford back, and things could change tremendously (ah, now I'm doing it too).
2019 stats: 4.31 xYPC, 1,438 ERY, -170 RYOE, -0.51 RYOE per attempt
The Rams should really be commended for landing on this list, especially after losing Joe Noteboom early in the season and needing a replacement so badly, they swung a deal (which could end up being a steal) with the Browns for Austin Corbett in the middle of the season. This might also be the most damning piece of evidence related to Todd Gurley's future, as we covered above with Atlanta. The league average in xYPC was 4.18 last season, so the Rams' mark of 4.31 is nothing to scoff at. Yet, the Rams weren't able to break 4 yards per carry with Gurley (and friends) in the backfield. Notably, the Rams landed in the top five for outside-run percentage at over 64 percent of all running plays in 2019. Perhaps having more trust in the interior linemen -- which, again, a lack thereof after losing Noteboom is understandable -- will produce better results for Malcolm Brown, Darrell Henderson and rookie Cam Akers in 2020. What's that old saying? Run north and south, not east and west? Yeah, that might help things in Inglewood.
2019 stats: 4.3 xYPC, 1,452 ERY, -66 RYOE, -0.19 RYOE per attempt
To round out the top 10, we welcome the Rams' SoFi Stadium roommates. The Chargers were worse up front in 2019, and no one will contest that. In fact, here are some numbers to back that up as we work toward peace on the matter. The Chargers went from a 12-win team with a 4.86 xYPC mark in 2018 to a five-win team with a 4.3 xYPC mark and a much-maligned pass-blocking unit. Everything got worse in the Chargers' final campaign in Carson, but it still wasn't enough to unseat them from the top 10 on the ground. Why didn't they win more games, then? Well, they were really close to winning a lot of them, but couldn't finish the job. Often times, a crushing turnover sealed their fate. Other times, they just weren't as effective as they should have been, and that includes Chargers fan heartthrob Austin Ekeler. He's the lead guy in Chargerland now, but he could be better. His RYOE per attempt was among the five worst in the NFL (among those with a minimum of 100 rushes) last season at -0.56, meaning that while the Chargers had some struggles up front, Ekeler also didn't reach the standard of expectation set by their successes. He's a versatile dynamo, of course, but he could be better carrying the football. While we wring our hands over troublesome Gurley stats, we shouldn't overlook Ekeler. If he can improve that, though, and the Chargers shore things up on the line -- which shouldn't be that hard to do, considering how they landed in the top 10 in xYPC in a down year -- we might be able to wash all of this away come fall.