Toronto Blue Jays v Kansas City Royals

Chris Davis is having a hell of a season. Turns out, he might be getting a little help.

No, not that kind of help. It might be that hitting coaches have a role in their player’s production. An amazing thought maybe, at least to old-schoolers rolling their eyes. Well, duh, that’s why we’ve had them forever. And yet, are we sure that the third-base coach adds and subtracts wins from the team’s ledger? How much impact does the manager have? And the pitching and hitting coaches?

Russell Carlton at Baseball Prospectus tried to isolate the effect hitting coaches have on their teams. It’s a difficult venture. There aren’t a huge number of hitters with large sample work before and after a hitting coach change — personnel changes as often as the coaching staff, and it’s hard to really nail down what a hitting coach does. Ask a hitting coach and they’ll admit they are there to tweak, not to revamp, at least normally.

After adding and subtracting — I’m sure that’s all it took — Carleton produced this overall leaderboard:

Best Hitting Coaches in
Overall Effect
Change in Runs over 6000 PA
from Ave. Hitting Coach
Clint Hurdle 91.44
Lenny Harris 88.25
Tim Wallach 87.76
Chili Davis 83.71
Mike Aldrete 66.77
Worst Hitting Coaches
in Overall Effect
Change in Runs over 6000 PA
from Ave. Hitting Coach
Dwight Evans -85.5
Lloyd McClendon -85.48
Paul Molitor -61.82
Gregg Ritchie -47.68
Jon Nunnally -42.7

Carleton provided some caveats after he published this leaderboard. Hurdle coached in Coors, Harris and Wallach only coached for two years. Chili Davis just started last year. But Kevin Seitzer just barely missed the list, and Alex Gordon gave all of the credit to his new approach to Seitzer in an interview with me. And some of the ‘bad’ names are reviled in hitting circles. It does pass the sniff test.

More interesting might be Carleton’s general takeaways. He found that hitting coaches can have a great effect, but that they mostly just change how aggressive hitters are, and if they focus on putting the ball in play or being more patient. This is the sort of thing I stumbled onto intuitively when trying to evaluate the work of Dave Hudgens early in his Mets career.

Of course, all of this was from a real life baseball standpoint, and it’s not easy to translate this over to fantasy baseball. Plus, it’s not clear if a patient approach is what fantasy owners want, unless they are in an OBP league. More walks *and* more strikeouts might mean a lower batting average. Plus, there does seem to be some role in how much a hitting coach teaches a hitter to pull the ball (for power) or go the other way (to get on base). And then how each hitter benefits from that specific advice. Think Dwayne Murphy and how his ‘grip it and rip it, pull the ball for power’ approach worked so well for some of his hitters. And then think of Emilio Bonifacio.

So let’s just look at Dwayne Murphy, since the Jays have had such interesting swings in fortune for some of their players. Let’s look at the players he coached that had at least two seasons before he got them, and then two seasons after. And let’s break this down into swing percentage, o-swing percentage, and some power stats for those players that we can compare, as those peripherals fit Carleton’s findings best. Murphy may not be the hitting coach any more, but it doesn’t seem like the philosophy has changed much under Chad Mottola anyway. At least we’ll know what Murphy did for the team, maybe.

Pre PA and Post PA refers to before Murphy’s tenure and the following seasons under his watchful eye.

Name  Age Pre PA Post PA O-Swing Z-Swing Swing Contact HR/FB ISO
Jose Bautista 32 1087 1054 4.4% -3.4% -1.1% -0.1% 3.3% 0.009
Kelly Johnson 31 1017 713 4.8% -0.2% 1.5% -7.5% 0.1% -0.056
Yunel Escobar 30 1171 1198 2.1% -4.2% -2.0% 0.1% 1.9% 0.007
Edwin Encarnacion 30 705 1174 0.4% -3.6% -1.9% 1.4% 1.0% 0.025
Adam Lind 29 1267 895 5.3% -0.2% 1.4% 0.4% -1.8% -0.049
Rajai Davis 32 993 825 4.0% -2.2% 0.2% -4.9% 1.9% 0.014
Travis Snider 25 595 242 6.8% -2.1% 2.1% 3.6% -4.7% -0.040
Colby Rasmus 26 1054 765 5.0% -3.0% -0.6% -1.7% -0.4% -0.020
Avearge 29 986 858 4.1% -2.4% 0.0% -1.1% 0.2% -0.014

Wow. Those are the differences before and after Murphy, and even if the effect is small, it seems real. It’s across the board. Murphy had them swinging at outside pitches more, even if it meant less contact. And for many of the hitters, it meant a boost in home runs per fly ball. It’s interesting that ‘grip it and rip it’ meant a zero change in swing percentage for the group, but you can see that some players took to the idea while others were more conservative. You can see that Murphy is definitely not afraid of a swing at a pitch outside the zone, though. Call him a ‘put it in play’ coach, or one that preaches aggressiveness.

What to do with this is a tougher question. If we could identify each hitting coach as an aggressive or passive one, we might be able to spot players that would benefit from them, maybe. But we’d still be grasping at straws. Because look at Colby Rasmus. With Murphy gone, he’s swinging and reaching less than ever, and hitting for career-high power… and also making less contact. For fantasy, that’s a good combo, perhaps, but it doesn’t fit the patient/aggressive dichotomy that we’re talking about. He’s being more patient but getting better results on his balls in play.

It’s like trying to look at Chris Young‘s line in the lens of Chili Davis being a top-five hitting coach. Each player has his ideal swing, and each player has their ideal hitting coach. Might take a smarter man than I to pair the two theoretically.

This stuff is hard.