The St. Louis Cardinals lost a lot of power this offseason. Brandon Moss recently signed with the Kansas City Royals. Matt Holliday left for the New York Yankees. The Arizona Diamondbacks claimed Jeremy Hazelbaker off waivers.
That’s a total of 60 homers that are off the St. Louis Cardinals roster that hit 225 in 2016. Put another way, 27% of the Cardinals 2016 home runs are no longer with the team. The long ball, which made the St. Louis offense so potent last year, will not be the focus of the 2017 team.
Yet, power is important. The ability to change the game with one swing can dramatically shift win probabilities and momentum. Thus, it will be important for the St. Louis Cardinals that the home run producers still with the team can repeat their 2016 performance.
Jedd Gyorko led the team in home runs this past season with a career high 30 dingers. His home run per fly ball rate (HR/FB) of 24.4% was a career high. This topped his previous career high of 15.9% set in his rookie season by more than 50%. That leads to two obvious questions: how did he do it? and is that rate sustainable?
Thanks to Statcast data, we can compare players’ batted ball quality to their results. For home runs, we can use HR/FB to measure a given player’s results. To compare 2016 results to an “expected” outcome, I ran a multi-variable regression using fly ball 2016 Statcast data to generate an expected HR/FB rate (xHR/FB) for 2016. The r-square value for this regression is approximately .65, which means the model explains 65% of total HR/FB variance for the season.
Following are the inputs and output for Jedd Gyorko:
As you can see, Gyorko outperformed his xHR/FB by a full 8.0% His xHR/FB of 16.4% still would have been a career high, but is also more in line with his career average rate. It also would have knocked his home run total down to about 25 instead of 30.
Nothing in particular jumps out about Gyorko’s fly ball profile. His xHR/FB rate of 16.4% was only about 3.0% better than the 2016 average HR/FB rate. However, he pulled slightly more of his fly balls than average and hit them at a slightly higher exit velocity than average. This would support a HR/FB rate a little better than the 13.4% average, but does not explain his 24.4% rate.
One factor that might at least partially explain Gyorko’s performance is his launch angles. While home runs can occur at launch angles between 18 and 44 degrees, the ideal launch angle is around 27 or 28 degrees (credit to Ben Markham at VEB). Using graphics available courtesy of Baseball Savant, we have a launch angle breakdown for Jedd Gyorko in 2016.
These graphics show the frequency that Gyorko batted balls at given launch angles. As you can see, his second highest peak occurs right around 30 degrees, which is in or near the HR sweet spot. Against only right-handed pitchers, this peak was even more pronounced. Also worth noting is that Jedd Gyorko limited his pop-ups and high fly balls, so more of his fly balls had greater potential to leave the park.
Additionally, a look at Gyorko’s fly ball spray chart provides another telling sign.
All but two of Gyorko’s home runs classified as fly balls were either up the middle or pulled. Additionally, while he rarely hit with “warning track power” when he pulled a fly ball, he did hit four that were wall-scrapers in most parks. His two home runs to right field barely cleared the fence as well. If a few of those traveled just slightly less, Gyorko might be looking at 27 home runs instead of 30. Though, he did have one down the left field line that could have easily been gone…
Overall, based on his batted ball profile, there is reason to believe that Jedd Gyorko improved his ability last year to hit fly balls at “home run possible” launch angles. If he can maintain a similar profile next year, it is very possible that he could keep up a HR/FB rate well above league average, even if he does see some regression.