Do defensemen play worse on their off-hand?

Steve Yzerman apparently has a problem. A right-handed defenseman problem.  The former Red Wing and current Team Canada general manager has too many talented right-handed defensemen at his disposal and is now stuck deciding between sending out a balanced lineup or one that might force some of the best hockey players in the world to line-up on the other side of the ice for a few games.

Admittedly, this is not really the type of problem that most people would consider a problem. But, as a responsible Canadian citizen committed to avoiding a national tragedy in Sochi, I wanted to help Stevie Y out by giving him as much information as possible before he makes his decision. With that in mind, I decided to look into whether pairing a lefty and a righty together really provides as much of an advantage as the media seems to suggest.

To do this, I took all the individual shift and play-by-play data from the 2010-11, 2011-12, and 2012-13 seasons and calculated how often each team sent out 2 same-handed defensemen (meaning one player must be on his off-side) vs. 2 opposite-handed defensemen (presumably not playing on their off-sides, although there’s no real way to check this assumption). I then pulled together each pairings on-ice goal and shot statistics, as well as individual goal, assist and shot numbers to look into whether having an opposite-handed pair provided a significant advantage.

In total, there were 2712 defensive pairs who played at least 1 second of ice-time together over our 3-year sample period (led by the Ryan McDonagh/Dan Girardi and Shea Weber/Ryan Suter pairs who both played together for over 1700 total minutes). Of the 264 defenseman, the sample definitely skewed to the left side, with only 98 right-handed defenseman (37.1%) vs. 166 lefties (62.9%). In terms of the ice-time distribution, the opposite-handed pairings received 61% of the total minutes, which seems in line with what you’d expect in a world where coaches prefer to keep players away from their off-hand, but can’t always do that (due to the lefties outnumbering the righties).

Looking at the data, however, it’s not really clear whether this strategy has much benefit.

Opposite handed pairs do seem to have a slight-advantage in both shot attempt and goal generation: they’re on the ice for more Corsi and Fenwick events for per 60 minutes of ice time, and they also recorded a higher GF/60 rate (Some of the deltas don’t match up exactly, but that’s just due to rounding). That 0.04 GF/60 advantage works out to around 2.97 extra goals over the course of an entire season, although that’s only in the most extreme scenario (all opposite-handed vs. all same-handed pairs). To put that 0.04 GF/60 in context, P.K Subban’s GF/60 since 2010 is 0.859, far above Karl Alzner (0.700), Jay Bouwmeester (0.709) and Dion Phaneuf (0.773), all of whom have been mentioned as possibilities to fill out the Canadian defensive corps should Yzerman elect to ice a balanced lineup.

In terms of the individual stats, we see a similar trend as with the on-ice data. About 50% of the GF/60 advantage that opposite-handed pairs appear to be the result of goals scored by defensemen, but again, the difference is very small. It’s also interesting to note that most of the increase in Corsi events we see (75%) is due to the defensemen themselves attempting more shots, and that most of the additional blocked shots are coming off the sticks of defensemen.

One thing to keep in mind is that we’ve been looking at all minutes, and all points in the tables above, regardless of the situation (EV/PP/SH). Pulling together the EV and PP data is a bit trickier, since there’s no easy way to separate out the even-strength shifts from the power-play shifts (the goals and Corsi/Fenwick events are easier). What we can look at, however, is how the total stats in each situation break down between opposite-handed pairs and same-handed pairs.

This is where I think the data starts to get a bit more interesting-if you’ll recall, our total TOI breakdown was roughly 61% opposite-handed vs. 39% even-handed, or roughly in the same neighbourhood of what we see for the even-strength data. On the power-play though, the situation changes drastically, with same handed pairs producing nearly half of the goals scored by defensemen, and similar split being seen in the other offensive metrics. I’d suggest that there are 2 possible explanations for what we’re seeing here:

1)      The distribution of ice-time between same-handed and opposite-handed pairings is different on the power-play than during even-strength play. Coaches may be more likely to put their two “best” defensemen together, regardless of handedness, on the power-play, whereas they may attempt to balance their pairings during even-strength play.

2)      The ice-time breakdown is the same in both even strength and power-play situations, but same-handed pairings are more effective on the power-play than during even-strength play. This doesn’t seem to be an unreasonable explanation: with more time to set up having a defenseman on his off-side for a one-timer may be more valuable on the power-play.

If I had to choose between the two, I’d lean towards the former over the latter: while the goal data certainly suggests that explanation #2 is possible, I think we’d probably see more of a split towards same-hand pairs in the 1A data if this were what was driving the PP numbers. If that’s the case though, it means that the difference in ES GF/60 rates is probably smaller than what we’d estimated above, lending more weight to the argument that playing on your off-hand isn’t necessarily that much of a detriment. Over the course of a short tournament like the Olympics, I think it’s far more important to select the best set of defensemen possible, rather than worrying about finding players to fill certain roles or maintaining “balance” throughout a lineup.