The Eye-Test and Dustin Byfuglien’s Impact on Jets

Dustin Byfuglien –like many of the Winnipeg Jets’ best players– is a pretty controversial player. You either love him and think he’s the best, or you just out right hate him.

Regardless of which category one falls in line with, almost all agree that the Big Buff has a tonne of talent in many areas but struggles in others. Very few will deny his offensive prowess, and almost everyone can remember at least one moment where a dangerous play evolves from a defensive miscue.

Which camp you lie in depends on your opinion of whether or not his strengths overcome his weaknesses.

Let’s take a look at the numbers.

Defensive Impact

Screen shot 2015-05-08 at 10.41.55 AM

Graph is all 5v5 minutes for 2010-15 seasons and courtesy of WAR-on-Ice. Shots are represented as a rate, with 1.000 being league average, for three zones representing different goal probabilities. Left is with player on ice, while right is player on bench.

Well this is interesting, no?

We see both the impacts that people talk about when they discuss Byfuglien.

We see how overall the Jets face far less shots against with Byfuglien on the ice than when he’s on the bench. We also see how Byfuglien’s defensive play impacts shots against, causing a greater percentage of shots against to exist in higher scoring probability areas.

Despite Byfuglien’s distribution being poor defensively, he has a positive defensive impact.

This is something the eye-test struggles with; there is a huge difference between a plus defensive player and a plus defensive impact. 

Offensive Impact

Screen shot 2015-05-08 at 11.35.04 AM

Graph is all 5v5 minutes for 2010-15 seasons and courtesy of WAR-on-Ice. Shots are represented as a rate, with 1.000 being league average, for three zones representing different goal probabilities. Left is with player on ice, while right is player on bench.


The offensive zone is Byfuglien’s bread and butter, and we see the extremely elite impact he has here.

The Jets have been below average in all three regions with Byfuglien on the bench but above league average with Big Buff on the ice.

Overall Impact

Screen shot 2015-05-08 at 12.41.07 PM

The previous graphs already display how Byfuglien’s overall impact is a net positive.

However, the largest impact comes from the lowest danger area due to Byfuglien being a high volume shooter and also his inability to force shots from the outside.

This could mean that while regular shot differentials are correct in Byfuglien being a net positive player, there is a possibility that they over exaggerate the extent of his positive impact.

Luckily we know the difference in goal probability for each range and can then use this to create a weighted shot model giving the expected goal rates.

(note that the method used here makes 1 no longer league average, but rather 0.02 for LD, 0.04 for MD, and 0.09 for HD)

Screen shot 2015-05-08 at 12.47.04 PM

While Byfuglien’s biggest difference in terms of shots is his impact in the low danger areas, his actual largest impact in terms of expected goals is within the high danger region.

It should also be noted that Byfuglien has near 3/4 of a season worth of ice time as a forward skewing the results. As a forward, Byfuglien’s results have been far, far worse than as a defender.

Closing Thoughts

The common eye-test can deceive because it’s just good enough to be dangerous.

It genuinely notices specific instances and that occur and it can get a general idea of what’s going on in particular facets of the game. Where it struggles is giving a measure to those events and facets. It struggles in knowing which impacts win the tug-o-war.

There is a David Tippett quote that I have used far to often (but let’s show it one more time):

We had a player that was supposed to be a great, shut-down defenseman. He was supposedly the be-all, end-all of defensemen. But when you did a 10-game analysis of him, you found out he was defending all the time because he can’t move the puck.

Then we had another guy, who supposedly couldn’t defend a lick. Well, he was defending only 20 percent of the time because he’s making good plays out of our end. He may not be the strongest defender, but he’s only doing it 20 percent of the time. So the equation works out better the other way. I ended up trading the other defenseman.

I’ve often used this quote to show how and why a puck moving defensemen may have a better defensive impact than a superior defensive defender.

Of course, that may not always be the case. The opposite can be true as well. The impact of a player’s shot distribution (or quality) may overpower the player’s impact on shot rates (or quantity).

Unfortunately for the detractors of Byfuglien, that is not the case here.

  • The Last Big Bear

    Byfuglien could be a Norris contender, if he played in a major Eastern conference market, and wasn’t shuffling between roles and positions from month-to-month, and season-to-season.

    I don’t know if I’d describe myself as a “fan” of Byfuglien, but his impact is undeniable, and he passes the eyeball test to me with flying colours.