Departing the Fly Ball Revolution — Apr 20, 2021

Yesterday, I listed and discussed the hitters who had raised their FB% marks by at least 10% versus 2020. Let’s now switch gears to those hitters who have seen their FB% marks decline by at least 10%. Remember these are still very small sample sizes, so the odds are the majority of these hitters return to their normal batted ball distributions by the end of the season. Still, it’s worth monitoring these names as FB% changes could have a big impact on a hitter’s fantasy value.

There has already been discussion about the changes we have seen in Joey Gallo’s underlying metrics, and boy are there a lot of them. The FB% decline is significant for a guy who sits with a career 28% HR/FB rate. Once again, the sample size is pretty small here, but it’ll be fascinating to watch how his season progresses.

After a solid 2019 and breakout short season in 2020, Anthony Santander has gotten off to a painfully slow start. He already doesn’t walk much, so when he’s striking out more than ever and his BABIP has plummeted, it means he’s rarely been on base. His HR/FB rate has been fine, but he simply hasn’t hit the ball in the air enough. So the good news is that his power remains strong, but everything else under the plate skills umbrella needs to turn around.

Well gosh, J.T. Realmuto, Corey Seager, and Brandon Nimmo are all sitting there with sub-20% FB% marks! All three earn much of their value from home runs, so if they ain’t hitting the ball in the air, it’ll be difficult for them to contribute a whole lot of value.

Don’t panic too much if you’re a Bryce Harper owner, as he’s merely traded fly balls for line drives so far. That’s perfectly fine for overall production, even if it’s unlikely to last. You really only want to worry when it’s the GB% that spikes at the expense of flies.

LOL at Eric Hosmer reverting right back to his worm-killing ways. Last year, he posted a FB% above 30% for just the third time, making us wonder whether he’ll finally remain above that threshold in the future. The early returns say no and that 2020 was the small sample fluke, but of course 2021 is an even smaller sample. But given his history, there’s no reason to think his FB% will jump from its current mark as he has always head-scratchingly been an extreme groundballer, despite his ample power. If I were an owner, I would want the fly ball Hosmer, not the ground ball one.

Rhys Hoskins has been one of the most fly ball heavy hitters in recent years, as his career average sits at 50%. While he does possess above average power, it’s probably not enough to justify hitting so many fly balls. This year, everything in his skill set has changed, and perhaps this is a more optimal FB% for his skills. Unfortunately, he stopped walking and is striking out more than ever before, so it’s been a bizarre start to his season.

Aaron Judge’s FB% has bounced around throughout his career, sitting above 40% several times, but also as low as 32.4%, so this dip isn’t as noteworthy as the Diff column would have you believe, at least based on history. However, since Judge sports a career 32.7% HR/FB rate, obviously you want him to hit lots of fly balls, so it’s noteworthy for his fantasy value. What’s also curious is last year his walk rate plummeted, as he was thrown a higher rate of strikes versus 2017-2019 and he coaxed a 3-0 count far less frequently. So far early on, his walk rate hasn’t budged off last year’s low. That will have the effect of reducing his runs scored as he ends up on base less often.

Max Muncy seems like an established veteran, but he’s actually never recorded more than 500 at-bats and has just once (that same year) recorded more than 500 plate appearances. But over the small sample of seasons we have, he’s been a fly ball hitter, as this is his first sub-30% FB%. The good news is that some of that is due to trading flies for liners, as his GB% isn’t significantly higher than his career mark.

Since 2016, Mike Trout’s FB% has risen each season, ultimately peaking at least year’s 50.3% mark. We had become accustomed to the extreme flyballing Trout, but his current season mark is actually barely below his 41.2% career mark. Also, he’s another line driver, as his LD% sits at an elite 28.6%, which would be a career high. As is usual with Trout…he’ll be fine.

The funny thing about the decline in Adam Eaton’s FB% is he now sits with an amazing 42.9% HR/FB rate .Obviously, Eaton doesn’t have the power to take advantage of a high rate of flies, so you want him hitting more grounders. But I don’t know if a rate of 60% is optimal for him or if he’s better off near his career average just over 50%.