Rockies' Nolan Arenado, Trevor Story showed positive signs this spring

Spring training statistics don’t tell the whole truth about a player, but that doesn’t mean they’re lies. Things like batting average and home runs during spring training aren’t any more revealing than a given player’s four-week run during the regular season. In that respect, Nolan Arenado’s spring batting average should be looked at the same way as Charlie Blackmon’s from April 2014. It’s nice, but everyone knows it’s a product of small sample size variance. That’s not the case for all spring training stats.

Last year, Dan Rosenheck of The Economist identified some spring training stats that do provide hints as to what a player might do during the regular season. A position player’s walk rate, strikeout rate, and isolated power (ISO, which is slugging percentage minus batting average) can be trusted with a smaller sample size. When compared to a player’s projections for the season (as August Fagerstrom did for some players here), they might provide a glimpse at what is to come. Let’s look at what these stats tell us about two of the most compelling position players for the Rockies: Arenado and his left-side partner, Trevor Story.

Let’s start with Arenado.

First, Arenado will not post an ISO above .400. That’s not how we should interpret that figure. What it does mean is that we should believe in the power he exhibited during spring training and, by extension, last year. In 2015, Arenado posted an ISO of .287; however, he’s projected to have an ISO of .235 this season. In other words, the projection expects regression, which is expected. Arenado’s spring training ISO is a challenge that essentially says, "maybe not."

Arenado’s walk and strikeout rates tell a mixed tale. For those expecting and/or hoping for Arenado to improve his walk rate this season, his spring training indicates that it’s not going to happen. His 2015 5.1 percent walk rate looks like it might be roughly repeated this season. But if Arenado can improve on his strikeout rate, which his spring training performance suggests might happen, then the lack of walks will matter even less. He had a 16.5 percent strikeout rate in 2015, which is already above average. Moving it closer to 10 percent means more balls in play. For someone who hits the ball as well as Arenado, that’s a very good thing.

These are small things that provide some hints regarding how one of the best players in the National League can remain that way, though somewhat differently. Story is more of a mystery. And unlike Arenado, Story’s spring outdoes his projections across the board:

Story won’t have an ISO above .400. Like Arenado’s exorbitant spring training ISO, it tells us that he’s someone who should hit a lot of extra base hits in the big leagues. That’s a great sign, but the other two figures are even better signs. Strikeout rates upwards of 28 percent aren’t uncommon anymore, but only Kris Bryant and Chris Davis types can really get away with them because they bring a ton of power. Story has pop, but he’s not quite the power hitter that Kris and Chris are. It would be huge if Story can keep his strikeout rate closer to 20 percent, which is about average.

A walk rate approaching 10 percent would be enormous as well for Story, as well as for the Rockies. The Rockies as a whole have been very bad at taking walks in recent years. This is a problem because on-base percentage is a key indicator of offensive success—you know, because it leads to scoring runs. It wouldn’t be terribly surprising if Story can do it. Aside from his 5.8 percent walk rate in 275 plate appearances at Triple-A last year, Story posted walk rates ranging from 8.1 to 14.2 percent during his minor league career. Again, Story’s spring doesn’t mean that he’s going to have a walk rate of 10 percent this season; however, it means that he has a good shot of outpacing his 7.6 percent projection.

We should ignore the spring batting averages and home runs. But that doesn’t mean we should throw a wet blanket over Cactus League performances Arenado and Story had. Some of the other stats indicate good things to come. Regarding Arenado, we really don’t learn a lot. His spring means he’s good; we already knew that. It’s different and more important for Story.

The takeaway from his spring training? Believe it.