Kris Bryant: an all-time great

Kris Bryant’s first year in the majors was a remarkable one. The Cubs third baseman posted the ninth-highest fWAR ever for a rookie since 1920 and rightfully won the National League Rookie of the Year award. Despite his success, there was some concern about his 30.6 percent strikeout rate — the 30th-highest strikeout rate among rookies who amassed 300 PA in the live-ball era. A strikeout rate that high isn’t necessarily damning, especially in this day and age, but it does drastically decrease a hitter’s room for error, so Bryant made some adjustments to his swing. He was hoping that a flatter swing would allow him to hit for not just more contact overall, but contact that would enable him to drive more balls in the ideal launch angle. His work paid off.

For the purpose of this article, I want to talk about strikeout rate compared to league average and scaled to 100 — we’ll call this K%+. Since Bryant’s 2015 strikeout rate was 50 percent higher than league average, his K%+ was 150. He brought that number all the way down to 104 in 2016, or essentially league average. That’s a great improvement, right? Wrong! It’s a super-duper, trained-with-Yoda-on-Dagobah, historically great improvement. Dating back to 1970 (because I had to include Mike Schmidt for obvious reasons), here are the greatest improvements in K%+ from a player’s rookie season to his sophomore season.

Regarding the table: Some of the players’ rookie seasons spanned parts of two seasons, hence their age being represented as a fraction. Also, although a poor K%+ is stated as a number over 100, the improvement column, marked diff, shows improvement as a negative number.

Players usually experience an increased strikeout rate when they make the jump from the minors to the majors. According to the most recent aging curve I could find, strikeout rates improve through a player’s age-25 season and then begin a gradual decline; that means the more a player cuts into his strikeout rate by age 25, the better. Bryant has yet to play in his third season, which will also be his age-25 season, but now that we have some historical comparisons, let’s see if we might be able to glean some insight into whether Bryant’s improvement in this area is sustainable by checking in on the comps to see how they did in their third seasons.

While the numbers vary player to player, as a group these players gave back a little of the improvement they made, but they basically recreated their sophomore seasons, posting a K%+ of 120 in their third year compared to 116 in their second year.

Bryant’s year-to-year improvement can be painted in an even more glowing light if we accept that hitters trade contact for power and vice versa.

Bryant’s ISO catapulted from .213 to .262, and he joined Mike Schmidt and Barry Bonds as the only two players on the list to see an increase in ISO from their first season to their second. I won’t pretend like that’s enough evidence to forecast 100 WAR for Bryant’s career, but since he debuted (in the Mike Trout era), he’s been absolutely extraordinary. Here’s a snapshot of how he ranks in a few important categories:

That 15.0 WAR is pretty significant. Going back again to 1920, here is a list of players who have accrued as much WAR as Kris Bryant through two years of service time.

As I am something of a congenital Cubs fan, this type of revelation excites me. You see, many of my dad’s childhood summer days included making the voyage from his father’s pipe fitting shop to Addison & Clark. Whether it was by way of the L, a car, or his bike, it didn’t matter, he just wanted to watch Banks, Santo, Williams, and Jenkins play baseball in the Friendly Confines. He even spent his senior ditch day in the bleachers of Wrigley Field. I mean, after every Cubs win in the World Series this past fall, this is what the front of our office building looked like:

So allow me to confirm what you’ve probably inferred: Cubs fans are overwrought with joy and teeming with optimism over a potential dynasty. A lot of that starts with (though doesn’t end with) their franchise third baseman. While we can only dream of a future, Bryant’s already helped deliver to Bleacher Bums everywhere the feeling they’ve been dreaming of for generations...

This.