August 18 2015 07:38AM
Photo Credit: Bill Streicher/USA TODAY Sports
Some of the most important work in the field of hockey analytics has focused on how player performance changes over time.
In a salary capped league teams need to pay attention to, and understand how, the aging process impacts future performance, since these factors can and should influence contract decisions. A bad bet on a player whose performance is declining can cripple a team's cap structure for years to come.
In part two of this series, designed to take an objective look at how contending teams are fashioned (read Part 1 here), we'll dig a bit deeper into the aging process and see what successfully constructed Stanley Cup winning machines can tell us about how contending teams navigate the age-old conflict with father time.
Some of the most influential work in this area was performed by Eric Tulsky, who looked at aging from a number of different angles, including the impact on player's shooting percentage over time, and Gabe Desjardins who looked at points per game.
Both analysts found that players tend to peak from ages 24-26 in terms of the specific statistics they researched (shooting % and points per game), but I thought it would be worthwhile to see how overall player performance, as measured by goals-against-replacement, changed over time for forwards, defensemen, and goalies. A summary of the methodogy I've borrowed from Eric Tulsky can be found here.
As we might expect, goals against replacement shows a trend consistent with other prior research. On average, forwards are in their prime between 22 and 26. Of course, we all remember the exceptions like Ray Whitney and Martin St. Louis, but players like this are just that - exceptions.
To apply this concept, I thought it would be worthwhile looking at an example of a recent signing from this summer - the extension of Brandon Sutter for a 5 year contract at an AAV of $4.375M/year.
Sutter just finished his 25 year-old season, and over the past four years his GAR has ranged between -0.55 (2013-14) and 5.5 (2014-15), so I decided to look at all forward who scored in that range in their 24 and 25 year-old season at look at their average GAR over their 26 to 30 year old seasons to get a sense as to what to expect from Sutter throughout the term of his contract.
While we can see that there are definitely examples of players who performed very well in this peer group, specifically Filppula, Bergenheim, and Nielsen, the majority of the players in this group saw their performance decline significantly, and only 14 of the 26 players played all five NHL seasons between the ages of 26-30.
Of course, Sutter could buck the odds, like Valtteri Filppula, but chances are what we've seen from him is what we should expect going forward, which is a player who GAR ranges between -1 to +4, before his games starts to deteriorate with age. Expecting him to be a foundational part of the team going forward is a bit of a stretch, but there's nothing wrong with this level of contribution in and of itself over the course of the next 5 season. That said, there is a valid question with respect to whether this is an efficient use of salary cap, but that's a blog for another day.
On the other end of the spectrum, a definite bright spot for the Canucks is Bo Horvat, who had a GAR rating of 0.23 in his rookie year last year. Because of his age, and the fact that the GAR ratings only go back to 2005-06, we have a relatively short list of comparable players for him, but that list includes the following players (GAR of -1 to 1 in 19 year-old rookie year):
This graph surprised me somewhat, in that I had expected to see defensemen develop a bit later than forwards. In fact what we're seeing is very similar, in that there appears to be a definite peak, on average, at age 24.
The most significant recent Canucks defense signing, at least in financial terms, was the 3 year $3.6M AAV extension given to Luca Sbisa, so I thought I'd use that as a test drive for GAR. Sbisa is an interesting case because he's had a negative GAR for each of his 7 NHL seasons, meaning that he's never been above the level of a replacement level player over the course of his entire NHL career. As there were no other defensemen that met this criteria - most who had trended in this direction had their NHL dreams halt abruptly - I used defensemen with a negative GAR in their 22, 23, and 24 year seasons to develop Sbisa's peer group:
Of the 6 players who fit the profile, four went on to play the next three seasons (i.e. the Sbisa contract period), whereas two did not play in the NHL, having seen their dreams end after their 24 year-old season. The upside for Sbisa is that he turns around his negative GAR trend, like Matt Greene who developed into a reasonably useful defenseman in his age 25-27 seasons.
On the other end of the spectrum, while his game is quiet and unassuming, Chris Tanev is establishing himself as one of the better young top-four defensemen in hockey. Like most advanced stats, GAR is a big Chris Tanev fan, crediting him with a GAR of +9.7 last season. The Canucks smartly signed Tanev for 5 years at an AAV of $4.45M, which could prove to be a bargain if he continues on his current trajectory.
Here are his closest peers based on his GAR in his 23 and 24 year old seasons (GAR +5 to +15):
There are a couple of minor differences in the goalie graph as compared to the two graphs for skaters.
Goalies rarely win starting jobs in their early twenties, so we see a bit of year-to-year variability in their GAR ratings during their 20's, which is magnified a bit by the lower sample size of goalies in general. Still, the overall trend is consistent, with their prime appearing to extend until age 29 when the impact of aging really start to set in. We see a bit of an anomaly for age 36, where Tim Thomas' 45 GAR 2010-11 season single handedly brought up the average for that entire age group.
The Canucks biggest investment in goal is of course Ryan Miller, whose 3 year, $6M AAV contract signed last summer has him signed as a Canuck through to his 36 year-old season. I decided to look at how his peers performed in their 35 and 36 year-old seasons.
We all recognize that Ryan Miller is no longer the Vezina calibre goalie he was in his 20s. That said, he's been reasonably effective over the past five years, averaging a GAR of 8.6 over this period, although last year represented the low water mark of his career with a GAR of -3.12.
So I decided to look at goalies with a GAR between -4 and 15 in their 33 and 34 year-old seasons as Miller's peer group:
It's not a flattering group of cohorts for Miller...
Five of the six players in Miller's peer group completed their 35 and 36 year-old seasons in the NHL, although only Nikolai Khabibulin managed to maintain a positive average GAR over this two-year period. Coming off of a significant injury last season, it may be a tall order to expect Miller to bounce back to his pre-2014-15 GAR levels, and with the predictable impacts of aging at play, the onus is on Jacob Markstrom to not only establish himself at the NHL level, but perhaps to take on a larger share of the workload.
Markstrom has yet to show himself to be a positive GAR goalie at the NHL level, but that said he closest comparables (-15 to 0 GAR in 23 and 24 year-old seasons) include Justin Peters, Brian Elliot, Darcy Kuemper, and Ben Bishop, so there's some room for optimism.
On one side of the coin, Horvat, Tanev, and to a lesser extent Markstrom provide some degree of optimism - maybe the Canucks at least have some vague semblance of a core to build around.
On the other side is a grimmer portrait, that of an aging team with too many players-in-decline signed to inefficient contracts. While we obviously hope that Sutter, Sbisa, and Miller turn out to be the exceptions rather than the rule, these recent signings and extensions underscore a concerning pattern that this management team may not be bullish enough in their consideration of the impact that aging has on player performance.
In the Canucks most significant recent signings at each position, the Canucks have allocated $12.9M, or 18% of the 2015-16 cap to three players that we can expect will have very little positive contribution to the club's overall team GAR.
In my next post, I'll explore management of the salary cap, in the context of goals-above replacement.
Others in this Series