How many years of productivity do Thornton and Marleau have left?

If the Detroit Red Wings somehow do manage to miss the playoffs this season, preseason prognosticators who have been predicting that team's demise on a yearly basis ever since Steve Yzerman's sweater retirement ceremony can finally pat themselves on the back and move on to a new target: the Sharks. It's likely they're already doing so, or would be if lockout purgatory weren't keeping many who cover the sport from in-depth discussions about the coming season, with last year's 7th-place finish seen as evidence of an imminent collapse.

Realistically, rumors of San Jose's demise will be based on the predicted decline of the top two scorers in franchise history, Joe Thornton and Patrick Marleau. Two players alone might not make a team but considering the impact that duo has had on the Sharks over the past six years and the fact that Dan Boyle is on the wrong side of 35 makes the team's aging stars an interesting source of debate, centered around how much longer Thornton and Marleau have left as legitimate first-liners. It's obviously impossible to answer that question conclusively without a crystal ball but it is possible to look at historical comparables to make some educated guesses about what the Sharks' captain and former captain's career trajectories might look like from here on out. After the jump, we'll take a look at similarly productive players to Thornton and Marleau throughout NHL history to see how long it took them to fall off the map.

For what it's worth, it should be noted that this is fairly primitive analysis that focuses purely on offense and compares across a wide variety of eras but I think it still has some worth. For both players, I looked at their total production from their age 30 season to their age 32 season (defined by how old they were on February 1st of any given year) and examined where that stacked up compared to the production of every player in league history between the ages of 30 and 32 (really well, for the record--players like Gordie Howe, Stan Mikita and Steve Yzerman showed up as comparables to Thornton while Brendan Shanahan, Brett Hull and Mario Lemieux were on Marleau's comparables list). Since overall points are probably a better measure of Thornton's value while goals are more pertinent to Marleau, I compiled a list of every player in NHL history who scored within 20 points of the 236 Thornton racked up from 30-32 during their own 30-32 aged seasons and then looked at how many points they scored each of the next five years of their career. I did the same for every player who scored within 10 goals of the 111 Marleau buried from 30 to 32. The results are as follows, starting with Thornton:

• Again, the group as a whole suffered a pretty sharp decline going from averaging 37 goals a season from 30-32 to 31 at age 34 and just 26 at 35.
  As we see in the chart of Thornton's comparables, the numbers seem to balance out after that but that could be as much about survivorship bias as anything else--the only players who even make it to 36 in the NHL are ones who are still productive.
• It really is incredible how prolific Marleau has been the past three seasons when you look at the names that show up on this list. /

So what does this all tell us? Well, nothing too unexpected--even players who have historically been as productive in their early thirties as Thornton and Marleau tend to tail off pretty substantially in their 33- and 34-year-old seasons, the former of which the Sharks' duo are slated to begin this year. This further underscores the importance of the organization keeping a keen eye towards the future and establishing a concrete plan for when Thornton and Marleau can no longer carry the mail on the team's top line. A younger secondary core of Joe Pavelski, Logan Couture, Marc-Edouard Vlasic and Brent Burns is already in place but there's no question they need to be supplemented with further talent for the team to remain competitive. Fortunately, this data also indicates that there's a good chance Thornton and Marleau can continue to be those support players if the team chooses to keep them around past their current contracts since players as good as they are have tended to provide at least second line-caliber offense into their late thirties.