How might George Springer’s bat age with the Blue Jays?

With George Springer now under contract with the Blue Jays for the next six years, a big determinant of how the tenure works out will be how his offensive production holds up as he moves into his 30s. Springer has been an impact bat essentially since he broke into the majors, emerging as elite the past few seasons, but whether, and how, long he can maintain that level is quite literally a $150-million question.

On Friday, I broke down his offensive profile in terms of the four major components of overall offensive production (strikeouts, walks, power, contact quality/BABIP). To summarize, Springer has a really well-rounded profile. Starting from 2017, he significantly reduced his strikeout rate and has maintained that, and then in 2019 there was a further power breakout which took him to another level, though representing a smaller sample.

Thus I started with a comparison set of all hitters since 1970 with at least 2,000 PA in their ages 27-30 seasons, selecting for similarity along those four offensive dimensions (K%+, BB%+, ISO+, BABIP+):

Eliminating active players and a few others who aren’t appropriate comparison (mostly already declined by age 30) leaves the 27 above. It’s a really strong group overall, with some future Hall of Famers and a lot of Hall of Very Gooders. Like Springer, they walked a lot (25% more than average), struck out less (10%), hit for power (35%), and had average BABIP.

One note is that despite very closely matching each component, and these four components explaining almost 96% of the variation in wRC+, the overall 128 wRC+ of the group is well short of Springer’s 139. My best guess being that the “+” stats on FanGraphs aren’t park adjusted, and that may be adding some noise. Nonetheless, it’s a good starting point, and these hitters were generally very good into their 30s.

Over their age 31 to 36 seasons time horizon, they averaged 2,426 PA, about the same as they had in the prior four seasons. Their average production declined to a respectable 114 wRC+, working out to about 10 WAR. Looking at individual components, their plate discipline almost entirely held up, as did their BABIP. What did decline substantially was their power output, from 35% above MLB average to 14%.

Interestingly, if one takes the above sample and tries to achieve a better match for overall wRC+, it doesn’t really change the outlook. I eliminated all players below 125 wRC+, bringing the remaining group’s average to 135 from ages 27-30:

Surprisingly, the only component that changed was BABIP, now above league average (.317 for the group rather than .304). But the average of future production was a very similar 113 wRC+ over 2,300 PA, for a slightly worse WAR. The better BABIP ages away, and the decline in power is even higher, to 9% better than league average.

As noted above and in the initial profile profile post, Springer took another step forward in 2019 into the elite power ranks. From 2017-18, his his power was “merely” 20% better than league average (120 ISO+); since 2019 it’s been 60% better. That’s tied with Cody Bellinger for fifth among qualified hitters!

For the overall 2017 to 2020 and age 27 to 30 timeframe, that works out to the very good 135 ISO+ figure to which the comparison set was matched. But if he’s truly an elite slugger now, then that’s going to underestimate him going forward. Thus, I repeated the same exercise, but this time matching for players with at least 750 PA in their age 29-30 seasons:

This generates an even more elite set of comparisons, though again we see the pattern of matching each component well but significantly lagging the overall average (138 wRC+ vs. 154 for Springer).

Their aging was bigger, albeit from a much higher level so they still ended up more productive from age 31-36, with almost 2,700 PA, a 117 wRC+ and 12 WAR. In terms of components, their strikeout rate was unchanged, with everything else slipping. BABIP was only slightly lower, but power fell significantly from 57% to 28% above league average, and walk rate slipped in this group too; likely a function of now longer being an elite power threat pitched around to the same degree.

Overall, this gives some idea of how George Springer can be expected to age over his Blue Jays contract. If I’m right about the divergence between the overall production (park and league adjusted) and components (league adjusted), there could even be even a little more upside.