The Change: The Bad Fastball Bucket

I shop in the bargain bins when it comes to pitching, and I usually do okay. But there’s a pitfall to shopping in those bins, and it comes from velocity. Or lack thereof — the lightly touted, the guys with no pedigree, the guys you find in those bins, they usually don’t have big fastballs. Or they’d be the darling of every scout.

So what, you might say. If they have command and great secondary stuff, then they can ball. Look at Aaron Nola!

Yes, that’s true. But there are inherent difficulties with a bad fastball. So let’s rummage through the bad fastball bucket and see what we find.

First, let’s see how important fastball velocity is to one specific outcome: the home run. Because the conventional wisdom is that bad fastball pitchers give up more home runs. And the conventional wisdom is right, and yet it is also wrong.

I took fastball velocity from Baseball Info Solutions because they combine sinkers, two-seamers and four-seam velocity. I then correlated it to exit velocity on fly balls and line drives (2015 only), home runs, and home runs per fly ball. Yes, velocity is good, it helps suppress exit velocity. It also suppresses home runs per nine innings. But *how* it does that is important.

If you only look at the first two graphs, you might think it’s a cut and dry case. Fastball velocity helps the pitcher suppress exit velocity, which in turn helps suppress home runs per nine and other slugging outcomes. Case closed, especially since Mike Fast once found that every tick of velocity was worth .28 runs suppressed per nine innings.

Hold up, though. Mike Fast? The guy that works for the Houston Astros? The team that has the rotation with the worst fastball velocity in the league? Which plays in the one of the tougher home run parks in the league? Maybe we should look at this third graph.

Well, that’s interesting. It looks like fastball velocity has virtually no impact on home runs per fly ball. It explains less than half of one percent of the variation in HR/FB, and it’s not significantly related. That means that fastball velocity mostly has the impact of keeping the ball out of the air, no?

We aren’t dealing in strong relationships here. Yes, more fastball velocity means more ground balls, but the relationship isn’t super strong (.033 p, .0335 R`2). None of these relationships are super strong, even if the direction on most is what we expected.

Let’s form a conclusion before going to the leaderboards. Shopping in the bad fastball bucket is probably not as risky as it first seemed, since these relationships are not super strong. On top of that, by eyeballing the fly ball rate, we can mitigate our risk, since home runs per fly ball are not impacted much. Other things matter! That’s the last bit, and we’ll tackle it in a few interesting cases below.

Here’s a leaderboard of starting pitchers with fastballs that average less than 91 mph. That’s below average for a right-hander (92) and just about average for a lefty, so our bucket definitely will be full of fish with limp-ish fastballs. Let’s also cut all the people with extreme fly ball tendencies — those are the ones we might be most worried about.

That last decision cuts some interesting players from the list, by the way. Nicholas Tropeano, Drew Smyly, Jake Odorizzi, Collin McHugh, Adam Wainwright, Julio Teheran, Mike Fiers, Anibal Sanchez, Marco Estrada, Phil Hughes, Doug Fister and Mat Latos — yes, this group will have home run problems, all things being equal. That feels right, even though Smyly is killing it in a pitchers’ park.

Low Velocity Starters With Decent Ground Ball Rates

Name	FBv	GB%	K/9	BB/9	HR/9	HR/FB	BABIP	ERA	SwStr%
Masahiro Tanaka	90.5	59.6%	8.0	1.6	0.46	7.7%	0.250	2.29	13.7%
Jaime Garcia	90.3	59.2%	9.4	3.3	0.23	5.0%	0.237	3.05	11.0%
Alex Wood	90.7	57.4%	7.6	3.3	1.09	15.4%	0.324	5.18	8.3%
Dallas Keuchel	88.0	56.5%	7.8	3.9	0.61	10.7%	0.344	4.70	10.9%
Ubaldo Jimenez	89.6	55.3%	8.8	4.0	1.01	15.4%	0.366	4.54	8.2%
Felix Hernandez	89.7	54.5%	6.8	4.1	1.03	13.2%	0.218	2.27	8.7%
Aaron Nola	89.9	53.8%	9.6	1.6	0.59	9.7%	0.241	3.13	9.6%
Jon Niese	89.4	48.9%	6.5	3.4	2.25	23.3%	0.315	5.63	6.4%
Rick Porcello	89.7	47.6%	9.3	1.8	1.36	15.8%	0.242	2.95	7.8%
Ricky Nolasco	90.5	47.4%	8.0	1.2	1.17	11.4%	0.304	4.70	9.5%
Rich Hill	90.2	47.3%	11.0	3.8	0.48	6.5%	0.292	2.39	10.9%
Wei-Yin Chen	90.0	47.0%	5.9	1.7	1.23	13.5%	0.307	4.66	7.0%
Ross Stripling	90.5	46.8%	7.6	3.3	0.27	3.7%	0.271	3.82	8.6%
Gio Gonzalez	89.6	46.7%	6.8	2.4	0.49	4.7%	0.243	2.19	8.6%
R.A. Dickey	80.8	46.2%	6.3	3.4	1.13	12.2%	0.315	5.18	9.2%
Wade Miley	90.4	46.2%	6.6	1.9	1.18	12.8%	0.325	4.74	11.4%
James Shields	89.9	45.3%	6.8	4.0	1.2	13.6%	0.272	3.60	10.5%
Hisashi Iwakuma	87.6	45.0%	7.5	2.7	0.84	9.5%	0.328	4.19	9.4%
Drew Pomeranz	90.6	45.0%	10.9	4.2	0.53	5.7%	0.244	2.12	12.7%
Jerad Eickhoff	90.6	44.9%	8.4	1.7	0.99	10.8%	0.295	4.21	9.6%
Kenta Maeda	89.7	43.9%	8.3	2.4	0.71	7.9%	0.235	1.66	12.5%

Qualified starters this year with below average velocity and at least average ground ball rate (44%) this year.

Our eyes should immediately focus on the pitchers with high home run per fly ball rates. It would be tempting to blame their fastballs, but we know better now.

Sort the group by HR/FB descending, and Jon Niese jumps to the top. He’s obviously been unlucky. But that doesn’t mean he’s super useful once those numbers regress. He’s got a swinging strike rate that’s 50% worse than league average, his strikeout minus walk rate is poor, and his ground-ball rate is merely average. Over his career, none of his pitches is above average by whiff rates, and this year, he’s throwing a bad changeup even more often. Pass.

The next couple guys offer some hope. Rick Porcello is beasting and he could be even better. He’s had some homeritis the last two years, and with velocity down this year, it’s tempting to point in that direction. But he’s back to throwing the sinker more, the ground ball rate is growing, and the only worry is that his swinging strike rate and strikeout rate are out of wack. But he’s always had good command. I’d hold him in all leagues.

Alex Wood has been confounding so far this year. He fixed his release point, and then it started dropping again. He’s had equal numbers of gems, mehs, and stinkers. He seems to have to really choose between grounders and strikeouts. But! He shouldn’t really have a problem with homers, so his projections seem believable. That makes him a buy in deeper leagues, and a hold in 15 teamers and the like. Without the Ks, though, he’s not really a 12-teamer.

Ubaldo Jimenez, James Shields, and Wei-Yin Chen have been suffering homeritis for large parts of their careers, so it’s hard to make them picks to click on this evidence. However! This is Chen’s best ground ball rate of his career. And best home park. I believe in Chen.

Don’t let anyone tell you Felix Hernandez is going to give up bombs like this all year. Wade Miley is better than you think, too, and definitely a deep league hold. Jerad Eickhoff seems just about right, though perhaps a bit unlucky.

And Drew Pomeranz and Rich Hill on the other end? Curves have some of the best home run per fly ball rates in baseball. And they throwing a ton. If one is available in your league, pick him up. They’re doing the same thing.