Tuesday, 3 April 2012

The Upside Of Injury

Since Daniel Sedin was sidelined by Duncan Keith on March 21st, the Canucks have gone from crisis mode to cruise control, coasting to a 6-0 record since the injury. This could be a coincidence, but it could also be the result of a much needed shock to the system, in which the ugly injured can be alternatively viewed as a blessing in disguise. Let's take a look at the Canucks numbers in March before and after the injury.

Pre-injury, the Canucks had a March record of 3-5-1, somewhat disappointing for a Stanley Cup contender, and by the sounds of this city, the team was going to hell, but since the injury, the Canucks are undefeated. The game stats tell an even more intriguing story. The average goals for (GF) have only increased by 0.23, a rather insignificant number given the small sample size. So these wins must be mostly a result of the play from the other end of the ice, and in fact, they are. The Canucks goals against average (GAA) have improved from 3.11 to 1.16 since the injury, begging the question, how does the absence of  the Canuck's leading scorer lead to a decrease in goals against?

We can examine this by looking at two different factors. The average shots against have increased since the March 21st, so the numbers do not suggest a change in the defensive style of play, but instead in the performance of the goaltenders. Although Schneider's GA have only increased from 1.75 to 1.0 and SV% from 0.942 to 0.965, the more intriguing difference has been in Roberto Luongo's play. Luongo has improved his GA from 3.0 to 1.33 and SV% from 0.851 to 0.963. This could be coincidence, but if we go back to 2009 when Daniel was injured, we almost identical results- Luongo's GA improved from 3.0 to 2.15 and SV% increased from 0.835 to 0.915. Why is this? A shock to the system provides extra incentive for players to better themselves in order to fill the hole occupied by the injured player. This likely occurs at every position from forward to net minder, and as we see, the absence of the Canuck's leading scorer in fact led to a slight increase in average goals for (GF), suggesting the forwards' effort to increase their contribution to fill the goal gap. But the injury provides the same incentive to all players on the team, and in the goaltender's case, there is no such hole to be filled, so instead of maintaining roughly the same numbers, we instead witness a surge in statistical performance.

What does this mean? Confidence. Goaltenders will likely maintain this high level of play even when the player returns, as we can see in Luongo's play in 2009 when Daniel returned to the line up (his GA further improved to 2.07 and his SV% followed suit at 0.928 in the month following his return). And how about the rest of the team? Although the team stats, such as goals for, may have stayed the same during the absence of Daniel Sedin, individual stats have increased to fill the gap. With this growth, players too have gained confidence, and when the leading goal scorer returns, we can only expect a further surge in goals for. This is precisely what occurred in 2009, when goals for increased from 2.88 to 3.13 in the month following Daniel’s return.

This is a phenomenon that runs contrary to common intuition. What appears to be a negative incident turns out to be have a positive effect in the long run. The negative shock of Daniel Sedin's injury gave incentive for the entire team to play better in order to fill the gap. The team successfully did this as goals for have actually increased by a small margin, and given there was never a gap needing filling in goals against, Luongo's improvement can be seen as a net improvement of play. When Daniel returns, we can expect that the confidence that the team possess will allow them to continue at this enhanced level, and Daniel's return to the lineup will only add more offense, creating a larger margin between goals for an goals against, potentially resulting in more wins. This could not come at a better time for the Canucks given the proximity to playoffs. Of course, the surge in goals will only come if Sedin makes it back into the lineup, and the Canucks are undoubtedly a stronger team with him. But even without Daniel in the lineup, the argument can be made that at least goaltending will be better.


  1. Nice Research on the goaltending numbers. I would be curious to see some similiar looks at other teams that are playing without a key guy. Pittsburgh certainly would be a good case study. Or maybe a team that lost someone late in the year to an injury. At any rate I certainly hope you are right about the confidence remaining if/when Daniel returns to the line up for the play offs. In the meantime its been a pleasure to see these guys pull together as a team and really get themselves settled and in a "play off hungry" mood!

  2. Wicked read man. This is a perspective you don't see in the media and it's really well thought out. I think if Danny came back in the regular season the statistics would prove you right, but we all know that offensive numbers drop when you hit the playoffs. That said, I think the team will be better offensively but the stats won't show it.

    And don't pay those guys at CDC a mind you are doing everything right. Either post it pretending to be someone else without guilt, or post it as yourself without shame.

    Keep writing!

  3. Well written, I hope you're right!!!

  4. Nicely written man, great research and presentation. Let's hope the trends continue!

    1. "The average goals for (GF) have only increased by 0.23, a rather insignificant number given the small sample size. So these wins must be mostly a result of the play from the other end of the ice, and in fact, they are."

      Just a question... how come it's not too small of a sample size to say its goals against but it is to small of a sample size to say goals for?

      Nicely written blog, but the logic at times is a bit ermm muddled.

    2. An increase of GF by 0.23 may be attributed to randomness given the sample size, however the change in goaltending statistics are much larger and therefore suggest some sort of pattern or potential causality, which is what I argue is the case. But the increase in GF may not be random either, after all if 12 forwards all try to fill one player's spot it is conceivable that there will be an increase- however the number is too small for me to take conviction in this argument. Thanks for the question.