Stars or Depth? What Is The Best Way To Build an NFL Roster?

With the 2020-2021 NFL season now over, it is officially the offseason! To be fair, there really isn’t an offseason in professional sports- activity happens year-round!

As we get farther into the offseason, we will get to see how each front office goes about building their rosters. The best part about this? No two general managers are alike! Some will prioritize adding star talent through signings and trades, while others will sit back and accumulate as much roster depth as possible.

In this Super Bowl, plenty of star power was present on the Chiefs and Bucs. Both quarterbacks were elite-level talents, while players like Tyreek Hill, Travis Kelce, Chris Godwin, Chris Jones, and Lavonte David are amongst the best players at their positions. At the same time, both teams had a lot of rester depth, so that could be the reason for their success as much as their front-end talent.

So, should a front office worry about having star talent or accumulating roster depth? In a perfect world, they could have both, but with the salary cap and a limited amount of resources, it’s practically impossible to sustain a roster like that for a long time. With the Rams going seven years without a first round pick, and with several star players on the trade block, now seems like a great time to answer that question!

To answer this, we will be looking at data from the past three seasons- point differential, expected points added (EPA) per play, and EPA/play allowed. With this, we will compare it to the number of “stars” and “above-average” players they have, using Pro Football Focus grades. What constitutes as a “star” and “above-average” player varies by the position, though players with an 80+ grade in that season generally classify as a “star”, while an “above-average” player earned a better grade than the average player at the position. We will star by looking at how stars and depth affects offenses and defenses, before looking at how they affect the team as a whole.

Building an Offense

Offenses win championships in today’s NFL. Thus, building a unit tailored to score as many point as possible is a necessity for being a successful team consistently.

A quarterback is seen as the face of the franchise, and it is easy to see why:

However, because it is such a valuable position, having merely an above-average quarterback is not enough, though your chances of having simply an average offense depend on it. However, even having an 80-grade quarterback doesn’t guarantee much success, based on this scatterplot.

Rather, team needs to be looking for the elite of the elite at the position. The average grade among top-ten quarterbacks was 89.36, and as shown on the scatterplot, quarterbacks at that level generally guarantee offensive brilliance and aren’t given justice by this basic trend line. The only 90-grade quarterback to lead a below-average offense was Phillip Rivers in 2018.

Meanwhile, the 90+grade quarterbacks in 2020 were:

  • Aaron Rodgers (1st in EPA/Play)
  • Tom Brady (5th)
  • Deshaun Watson (9th)
  • Patrick Mahomes (3rd)
  • Josh Allen (4th)
  • Ryan Tannehill (2nd)
  • Russell Wilson (7th)

An elite quarterback is game-changing when it comes to building a championship offense. The fact that four of these quarterbacks were the final four remaining isn’t a surprise, and the fact that Watson led a top-ten offense despite having no support around him tells you all you need to know: an elite quarterback truly does elevate the players around him.

As for building around the quarterback:

Outside of the quarterback, there isn’t a specific way to build an offense in terms of quality vs quantity- either strategy can work. This further emphasizes how important the quarterback position is. In terms of the important of quality vs quantity at each position:

  • There was little extra value in having a star running back (r^2= .066) than having an above-average one (r^2=.044)
  • The R^2 values (roughly 18%) were about the same for the amount of star receivers, amount of above-average receivers, and the top-graded receiver.
  • There is little benefit in having one star offensive lineman, but if your top-graded offensive lineman is below a 70 PFF grade, the results aren’t pretty:

So if building an offense is all about having a star at one spot – the quarterback position – then shouldn’t front offices be focused on doing what they can to make sure they get optimal production from that position? If so, this makes investing at the wide receiver position critical:

I know that Patrick Mahomes struggled with his offensive line performing poorly in the Super Bowl, but the receiving corps’ inability to gain separation caused him to hold onto the ball for well over three seconds, so the blame may actually fall on receivers. In the end, a quality receiving corps is what a quarterback needs to do thrive, and if the resources aren’t there to build a top-notch offensive line, that’s a price you should pay to get elite playmakers. That playmaker, meanwhile, shouldn’t come at the running back position, while a sound defense doesn’t actually help a quarterback.

In essence, strive for excellence at the quarterback position. From there, you can add star talent or depth, but that should come at wide receiver or tight end. Ideally, you’d like to have an offensive line without any weaknesses, but until your quarterback is in place and he has perimeter weapons, that falls on the back burner.

Defense Construction

There wasn’t really an answer for whether stars or depth mattered more on offense, as it all comes down to the quarterback. Defense, on the other hand, provides us with a much different story:

With defense being so reactionary, it isn’t a surprise that stars don’t make as much of an impact (the correlations for the top-rated player at each position similarly show little correlation). Offenses can game plan to not only limit a defense’s best player, but also take advantage of their weak-link, meaning that constructing a defense is all about being as well-rounded as possible. In fact, I’d make an argument that a defense will more resemble the quality of their worse player than the quality of their best player.

Having a star defensive lineman such as Chase Young, Nick Bosa, Khalil Mack, etc. is something many front offices want badly, but really, there is little benefit in having a high-end talent there:

That’s quite the lack of a relationship, particularly when elite players at this position are being paid north of $25 million. For those believing Chase Young or Nick Bosa is too lofty of an asking price for Deshaun Watson, think again, as does the fact that even a player like Aaron Donald can only do so much. Depth on the defensive line, however, should be a more coveted quality:

Even when comparing the effects of the number of star d-linemen (r^2=.038) to this, it is clear that depth ultimately wins out. The more quality players you have on the defensive line, the less likely it is that an offensive line can deal with a strong pass rush; it is harder to double team one player when everyone on the defensive line is a quality player.

Given the market of defensive linemen, this also attacks a potential market inefficiency. It is easy to find value at this position by not shopping at the top of the market, and finding a healthy dose of affordable players and taking swings on them in the middle rounds of the draft is a smart way to get depth, rather than putting the team in a tough spot by overpaying for one elite trench player.

As for linebacker and defensive backs, the correlations are similar. High-end play is more important at those positions, particularly with defensive backs, as it is more about having non-liabilities at the linebacker position. There is potential some value for star talent in the secondary based on my findings, likely because an elite cornerback can help take away a top-end receiver, but really, defense is all about quantity rather than quality.

Overall Roster Construction

Want to know how valuable the quarterback position is?

*NOTE: Y-Axis is Looking at Point Differential

It may seem crazy that one star quarterback can guarantee more success than having an abundance of star non-quarterbacks, but there is a reason their Wins Above Replacement (WAR) is so much higher than any other position. Right now, Deshaun Watson is looking to be traded, and with this thinking, no non-quarterback can be untouchable for any team. In fact, if you aren’t the Chiefs, not calling the Texans about Watson’s status would be doing yourself a major disservice. On the other hand, the Texans can’t look at Watson’s situation as a way to trade him and be in a better position- it is practically impossible to replicate the value of a star quarterback.

With that being settled, are better teams built with stars or depth? We’ve already seen the correlation between star talent and point differential, but what about the number of above-average players?

This isn’t surprising, and correlates with the Super Bowl winners very well. Yes, the Bucs have star power, but they also had more than three talented receivers, a secondary loaded with depth, and no exploitable weakness.

As expected, offensive stars and above-average players had a greater correlation with point differential than that for defense, though splitting it between valuable and non-valuable positions didn’t show any difference. Once again, once you have the quarterback, nothing comes close to mattering as much.


In the end, building a roster with ample depth rather than front-end talent is the way to go.

However, it all comes down to the quarterback. The effects of having an elite player at the position are such than even simply having an above-average player or an 80-grade player at the position isn’t enough. There is no price that is too much to acquire a player of Deshaun Watson’s caliber, and unless you have Patrick Mahomes, not trying to acquire him would be silly.

This brings us back to another question: is the Rams approach smart? By this line of thinking certainly not. Matthew Stafford’s baseline as an 80-grade quarterback doesn’t guarantee they’ll be an elite team, while non-quarterbacks such as Jalen Ramsey and Brandin Cooks weren’t worth a combined three first-round picks. A singular first-round pick can be worth trading for an impact receiver or defensive back, but beyond that, there is little value.

In the NFL, we often cling too closely to specific star players. It’s hard not to be sentimental about this sport, which is why teams often go out of their ways to pay top dollar to extend their star players, while they aren’t as open to trading them as they should be. Yet, Aaron Donald, Khalil Mack, and other star defensive lineman have seen their prime years wasted by teams without quality quarterbacks. Star pass rushers aren’t the “quarterback of the defense”, and with football shifting to a perimeter sport, the trenches have never mattered less.

Get the quarterback, then worry about the receiving corps and secondary. From there, building as much roster depth possible is the way to go. It can be scary to pay a quarterback top dollar, but if he is capable of producing 90-grade seasons and elevating the talent around him, his value is practically unquantifiable. The team who acquires Deshaun Watson will be a very lucky team, while the Texans almost certainly won’t be able to replicate your value. Also, if you are a team with an elite player at a non-valuable position, such as the Steelers (TJ Watt), Saints (Ryan Ramczyk), Vikings (Danielle Hunter), among others, not trading them when you can get multiple first-round picks would be doing yourself a disservice. That is, if you’re in the business of winning Super Bowls, which can be done quicker than expected with a roster built correctly. Just ask Tom Brady and the Bucs.

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