Evaluating The Performance Of NHL Defensemen With Goals Above Replacement (GAR)


Defensemen are often times the most polarizing players in hockey. If you read comments from fans online, many times they are criticizing mostly defensive players, calling them pylons or other disparaging terms, because they’re not solid enough, defensively.

However, defensemen in the NHL are often times evaluated by their offensive output, as you can see by how the Norris Trophy race for the best defenseman in the NHL has panned out over the last decade.

Ideally, you would evaluate the performance for a given defenseman based on their role. If the player is an offensive defenseman, like John Carlson or Quinn Hughes, you’d want that player to have a high point production and a high-level of scoring chance generation. That being said, you don’t want your offensive defensemen to be absolute disasters on defense.

The same can be said for defensive defensemen. You want them to limit the amount of chances allowed and overall shot attempts against, but you don’t want them to constantly be in their own end, defending and not generating any scoring chances.

In this post I’ll lay out the best case for evaluating defensemen, and set some general guidelines for success. To learn more about the analytical terms used in this post, please check out our NHL Analytics Glossary. Statistics used in this post are courtesy of Evolving Hockey, Hockey Reference, and Natural Stat Trick.

Comparing Players To The League Average

Goals Above Replacement (GAR, you can read about it more from one of the creators of the statistic here) is likely the best way to evaluate the total value of a player in today’s NHL. You may be familiar with Wins Above Replacement (WAR), which was pioneered in baseball statistics. GAR is very similar. A basic definition from Pension Plan Pupets:

In concept, GAR is a one size fits all number that encapsulates how valuable an individual player is in terms of on-ice play, relative to a ‘replacement level’ player. A replacement level player is a player of a caliber such that they are readily available and can be acquired and played at a moment’s notice. Think along the lines of the players who shuttle waivers every year, or are your emergency callups from the AHL. A replacement level player is one of those. An example would be a player like Byron Froese – a good player in the AHL who becomes very limited at the NHL level.

Also, you can think of a replacement level player as a 13th forward or 7th defenseman.

GAR is a great way of encapsulating the total value of a player, looking at a wide range of statistics, including even-strength offensive and defensive performance, special teams performance, and the ability to draw penalties and stay out of the penalty box.

Calculating GAR

How is it calculated? Back to our friends north of the border for a general definition of the calculation:

player value is decomposed into six categories: even strength offense, even strength defence, power play offense, penalty drawing, penalty taking, and faceoffs. Value is calculated in each of these categories, usually by a regression-based technique, and summed up for each player. The drivers of value change depending on the category. Within even strength offense, the important drivers of value are scoring and shot generation (accounting for shot quality, competition, and teammates). For even strength defense, it’s all about shot suppression, again, accounting for shot quality, competition and teammates. Power play offense is largely about power play production, and the remaining three have obvious drivers. These are all summed up to get a total value for the player.

To show how well GAR works, try to think of the ten best defensemen in the league today. Here’s what Evolving Hockey calculates with their GAR valuation:

  1. Cale Makar (22.7 GAR)
  2. Charlie McAvoy (21.5 GAR)
  3. Devon Toews (20.4 GAR)
  4. Roman Josi (20.2 GAR)
  5. Victor Hedman (19.8 GAR)
  6. Nick Jensen (!!!) (19.1 GAR)
  7. Aaron Ekblad (18.1 GAR)
  8. Chris Tanev (16.9 GAR)
  9. Thomas Chabot (16.8 GAR)
  10. Adam Fox, Justin Faulk, and Oliver Kylington (tied at 16.5 GAR)

Obviously, there might be some surprises on this list, but I’d be shocked to hear about anyone’s top ten defensemen list that didn’t include Makar, McAvoy, Josi, Hedman, and Fox.

Why GAR?

Here’s why GAR is really effective at determining player value: it examines true on-ice performance. Nick Jensen was the best defenseman on the roster last season for the Capitals, and it wasn’t even particularly close. The defenseman with the second highest GAR on the team was Dmitry Orlov (9.8 GAR).

You might be thinking, Jensen was the Capitals best defenseman? That’s what the valuation is telling us from his performance last season. The real difference is, Jensen was extremely valuable, offensively, in terms of on-ice results. He didn’t put up a ton of points, but he was on the ice for the most ‘goals for’ during 5-on-5 play out of all the team’s defensemen and was on the ice for the fewest goals against. Additionally, Jensen routinely stayed out of the penalty box with only 21 penalty minutes in 76 games, which added 3.9 penalty GAR value to his overall valuation. Here’s how the Caps defensemen panned out in terms of GAR last season:

GAR Goes Both Ways

Interestingly enough, GAR is effective in determining negative value as well. Justin Schultz had the lowest GAR value on the team at -4.8. He struggled in even-strength offense and defense, which is what was observed on the ice. He was on the ice for eight more goals against than goals for and had meager possession stats.

Additionally, Schultz played in 28 more games this season than last season and scored four fewer points. That’s not exactly what you’re looking for from your team’s second option at offensive defenseman. His points-per-sixty minutes value dropped by nearly 50%.

GAR works well for evaluation because it brings a spotlight to the unheralded players like Jensen or Oliver Kylington, who had strong seasons by advanced analytical measures. The difference between the heralded and unheralded players is the ability to repeat performances. The players that typically lead the GAR valuations, year after year, tend to be the more heralded players that put together long stints of high performances.

Last Three Seasons

If we look at the last three seasons of GAR valuations for defensemen, we see a veritable who’s who of defensemen in the NHL:

  1. Cale Makar (55.1 GAR)
  2. Charlie McAvoy (51.6 GAR)
  3. Victor Hedman (47.2 GAR)
  4. Adam Fox (41.1 GAR)
  5. Roman Josi (40.6 GAR)
  6. Jaccob Slavin (40.4 GAR)
  7. Devon Toews (35.1 GAR)
  8. Ryan Pulock (33.4 GAR)
  9. MacKenzie Weegar (33.1 GAR)
  10. Jared Spurgeon (32.4 GAR)

The way we know this metric works is that at least 8 of the 10 names listed here are likely in most folks’ top ten defensemen list. On top of that, there isn’t just one type of defenseman represented here. There’s high-octane offensive defensemen like Makar and Fox. There’s also a big two-way defensemen in Hedman, and there’s more shutdown type guys like Slavin and Weegar.

Conclusion

GAR is one of the most encapsulating metrics for evaluating value of players in general, but also defensemen in particular. Defensemen have an interesting mix of roles and responsibilities that can affect their perceived value.

GAR measures the value that a player exudes in the most important facets of the game.  There are other metrics that can be used to generally assess value of players, but I believe GAR is the most robust means of evaluating overall season performance outside of typical box score performances, like goals, assists, and points.

By Justin Trudel

About Justin Trudel

Justin is a lifelong Caps fan, with some of his first memories of the sport watching the team in the USAir Arena and the 1998 Stanley Cup appearance. Now a resident of St. Augustine, FL, Justin watches the Caps from afar. Justin graduated with a Bachelor's of Science in Political Science from Towson University, and a Master's of Science in Applied Information Technology from Towson University. Justin is currently a product manager. Justin enjoys geeking out over advanced analytics, roster construction, and cap management.
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5 Responses to Evaluating The Performance Of NHL Defensemen With Goals Above Replacement (GAR)

  1. Anonymous says:

    This makes a lot of sense. There are a wide range of stats to evaluate defensemen. John Carlson is a great example. Tops in offense, but defense is a struggle.

  2. DWGie26 says:

    After comments from GMBM, I sense there won’t be a move for a center. I could see them making a value move (3-4M) for someone who can play 1LD so Fever can move down to 3LD. This will put LuJo in 7th spot which is probably best as he doesn’t have to be a daily player, but he will grow being around the pros and will get some games. probably pick up a league minimum 3/4RD as well.

    • steven says:

      I dont see them spending that much on one player. I think they will look to go on the cheap and/or use guys from Hershey and bank the money until the trade deadline unless Backy retires and they can sign Foresburg.

    • Jon Sorensen says:

      I like your plan and price for an LD. We’ve done several posts on just that. Also like LuJo at 7D to ease him into the mix.

  3. Anonymous says:

    The GAR ranking is pretty much exactly how I would rank them last season, I might have Orly a bit higher, offensively, and Fehervary a bit higher defensively, just based on the “eye test”

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