Evaluating the Paul Goldschmidt extension

The makeshift press conference at the Cardinals’ Spring Training complex in Jupiter–much like the Clark Street presser back in December–was met with what I would consider relatively tepid response from Cardinals fans considering the sheer magnitude of the news being announced. Of course, I am referencing one Paul Goldschmidt on both counts. The six-time All-Star selection, owner of four Silver Slugger awards, thrice a Gold Glover and top-three NL MVP vote getter, and bazillion-time [insert accolade] recipient en route to an overall run of production empirically unparalleled at first base since his breakout 2013 campaign.

Goldschmidt’s five year, $130 million extension–before even playing a regular season game with the club–surpasses Matt Holliday for the largest deal in franchise history. You’ve probably already been treated to various surplus value charts weighing the cost of the contract relative to the projected return on investment (for what it’s worth my homemade calculator spits out approximately $4 million in surplus value for St. Louis), so today I wanted to take a slightly different, albeit less scientific, approach to evaluating Goldschmidt, a 31-year-old first baseman’s, extension.

Baseball Reference’s similarity scores allow us to quantify the closest historical comparisons to any player at any given age using a variety of statistics. Again, this is by no means the most accurate way to predict future performance, but if nothing else curiosity begs the question: how did Goldschmidt’s peers fare as they worked deeper into their thirties? Ranked from most to least similar, here are the 10 most most similar position players to Goldschmidt through age 30:

1. Jeff Bagwell
2. Adrian Gonzalez
3. Mo Vaughn
4. Derrek Lee
5. Fred McGriff
6. Ted Kluszewski
7. Carlos Delgado
8. Larry Walker
9. Lance Berkman
10. David Ortiz

There is an array of talent here ranging from Hall of Famers and should-be Hall of Famers to players that, although quite productive, weren’t nearly as dominant when looking back on their careers. Given that all 10 of these players have completed their age 36 season, the year that Goldschmidt’s extension lasts through, we can observe how they regressed at the same age through their WAR per 600 plate appearances.

With the exception of the blip between 33 and 34–which can almost certainly be chalked up to the incredibly small sample size we are dealing with–the average WAR/600 more or less dips by half a win each season.

Applying that trendline to Goldschmidt, you get different results depending on what you set his baseline WAR as, or his level of production before you start factoring in age. Since he is still on the books at $14.5 million this season, Goldschmidt’s recently-inked extension doesn’t kick in until he is 32 in 2020, so let’s assume that he puts up his FanGraphs projection of 4.2 WAR in 2019. That leaves you with 3.7, 3.2, 2.7, 2.2, and 1.7 wins over the next five years: good for roughly $7 million in surplus value. However, if you hedge your bets for, say, injury risk and only peg Goldschmidt for 600 plate appearances a season (unlike the 658 that FanGraphs has him down for), the surplus value flip to -$9 million as you end up with two fewer cumulative WAR in that scenario.

Perhaps 4.2 WAR as the baseline projection in 2019 is too low. If we bump that up to 4.5 in 2019 before docking half a win each year, Goldschmidt then posts 15 WAR over the lifetime of the extension and churns out $20 million in surplus value. These numbers are noticeably sensitive, though. Case in point: if you take off a full win for age 36 as opposed to just one-half, for example, the surplus value dips back down to $11.6 million. Moral of the story: this stuff is an inexact science, and to be fully honest none of us truly know what the hell we’re doing when it comes to these types of cost analyses.

As far as Goldschmidt’s specific aging curve goes, one skill he could benefit from is his traditionally high walk rates. Of the 10 best (in terms of FanGraphs’ calculation of WAR) individual seasons from an age-34 or older first baseman in the previous 10 seasons, the average home run count was only 22 whereas the walk rate was a much more robust 11.7%. This intuitively makes sense as well. Plate discipline doesn’t erode the same way that raw muscle mass does, so players who can reach base and produce value in ways other than pure power will likely enjoy more graceful declines than their slugging-centric counterparts.

We can quarrel with the specific projection markers and surplus value numbers, but on balance the Goldschmidt extension looks to be a fair deal for all parties involved. Goldschmidt is locked in for the next six years and went from obscenely stupid rich to even more obscenely stupid rich while the Cardinals finally have their elusive star as a centerpiece to the roster. So in conclusion, Paul Goldschmidt is extremely good at baseball...and we’re now just two days out from watching him don the Birds on the Bat when it counts.