The Fujinami Conundrum

Tommy Gilligan-USA TODAY Sports

Just 15 pitchers threw 10 or more 101+ MPH four-seam fastballs in 2024.

There are a lot of pitchers who throw fast and only 15 find themselves qualifying here as repeatable flame throwers. Jhoan Duran did it 368 times! Behind him was Félix Bautista who anyone would guess can throw the ball fast after one glance at La Montaña. But, Shintaro Fujinami? He’s on the list? He’s a free agent? Surely some team could use a guy like that. So, why hasn’t any team ventured a bid on a reliever whose fastball velocity ranks in the 97th percentile?

Top 101+ Four-Seamer Pitchers by Count
Player Pitches Total Pitches Percent
Jhoan Duran 368 1017 36.2
Félix Bautista 118 988 11.9
Ben Joyce 80 202 39.6
Ryan Helsley 74 607 12.2
Justin Martinez 58 236 24.6
Jordan Hicks 46 1114 4.1
Shintaro Fujinami 46 1404 3.3
Aroldis Chapman 45 1008 4.5
Carlos Hernández 41 1251 3.3
Hunter Greene 25 2089 1.2
Andrés Muñoz 22 836 2.6
Abner Uribe 16 518 3.1
Trevor Megill 14 599 2.3
Nate Pearson 10 737 1.4
Mason Miller 10 609 1.6
SOURCE: Baseball Savant

We don’t have to dance around the issue. Fujinami being on this list simply means his fastball is fast and he has thrown it fast more than 10 times. That doesn’t mean it’s a great pitch. Sure, it grades out to a 107 Stuff+ score (physical characteristics of a pitch), good for 33rd among all pitchers with at least 70 IP, but its Location+ (ability to put pitches in the right place) is a paltry 92. PitcherList’s PLV scores Fuji’s fastball as 4.74, with an MLB RP average being 4.86. PLV is valuing Fuji’s stuff while discrediting his placement. So, is this article over? Is it simply that Fuji cannot command his fastball and everything else falls apart as a result? Not quite.

Fuji’s fastball misses bats. It has an overall swinging strike rate of 11.6% compared to an MLB relief pitcher’s average of 10.7%. When he puts it in the zone, his swinging strike rate jumps to 15.9%. Almost all of Fuji’s pitches garner more swinging strikes in the zone, except for the cutter. While that is typical by nature of pitches simply being swung on more often when in the zone, it’s the difference between in and out of the zone that stands out for Fujinami:

In Zone vs. Out of Zone SwStr% (Relievers)
Fuji In Zone SwStr Fuji Out of Zone SwStr League Average In Zone SwStr League Average Out of Zone SwStr
FF 15.9 6.7 12.2 8.0
FS 29.3 12.3 15.6 17.4
FC 11.7 19.1 11.4 11.1
Alex Chamberlain’s Pitch Leaderboard

You can imagine that cutters get swung on and missed and fouled off a lot out of the zone due to the shape of the pitch tailing in or out of the zone at the last minute. The table above might suggest Fujinami should continue to work the edges with his cutter but should move his four-seamers and splitters in the zone more often. But here’s what happens when does throw his splitter in the zone:

Splitters can be fickle, and Fujinami’s is no different. It has that great in-zone 29.3% SwStr, yet it can get crushed in the zone. But, that happens when you leave it smack dab in the middle:

Fujinami Splitter Heat Map

So, it’s not enough to write, throw it in the zone more often. No, it needs to be more like, throw it in the correct part of the zone more often. But it’s possible that Fujinami can’t do either of those things simply because he doesn’t know where his pitches will end up. He has always had an issue with command. Starting his career in Japan in 2013 with the Hanshin Tigers, Fujinami collected 1,300 innings pitched and put up career ratios of 4.1 BB/9 and a 9.4 K/9.

In his first season in the MLB he put up similar numbers; 5.13 BB/9, 9.5 K/9. A major league average reliever posted 3.7 BB/9 and 9.1 K/9. So, yea, he has issues with walking hitters but he had even more issues with giving up hits or walking more batters once the bases fill up. Fujinami’s 1.71 WHIP with runners on was well over the reliever league average of 1.34 (Men on Base). You wouldn’t know it by looking at his overall Zone% as it is almost exactly league average (42.0%), but you will notice that his Zone% is significantly worse than average in unfavorable counts:

Reliever Zone% When Behind
Fuji Zone% League Zone%
1-0 51.6% 54.0%
2-0 55.1% 59.2%
3-0 57.9% 66.7%

As pitchers fall further behind in the count they try to make up for by throwing the ball in the zone. Fuji does the same but is below what a league-average reliever does in each situation. That plays out as walks rather than strikeouts when he falls behind in the count at a worse clip than an average reliever:

K/BB, Shintaro Fujinami vs. RP League Average Bar Chart

So now, I present to you, The Fujinami Conundrum:

a pitcher’s stuff is better in the zone, but the zone cannot be found.

We hear so often about how nasty a guy’s stuff is and so many recommendations from data wizards to nasty pitchers is to throw it in the zone more because they can’t hit it. It’s never that simple. In Fujinami’s case, he’s better in the zone, especially with his fastball. When a pitcher falls behind, they need to rely on their fastball because it’s the simplest way to get back in the count. But, without fastball command, everything else is lost. Fujinami is trying to throw his fastball in unfavorable counts, just look at how much he relies on the fastball when behind:

Fujinami Pitches by Count

Yet, it is not effective due to his lack of control. Does this relate to other players? I’m a fantasy baseball writer so I’m now supposed to show you a list of players who fall under The Fujinami Conundrum. It’s also not worthy of an underlined presentation as above unless it applies to other pitchers. So, here are the relievers whose four-seam fastballs have better swinging-strike rates when in the zone, yet their Zone% is worse than average in unfavorable counts (1-0, 2-0, 3-0):

The Shintaro Conundrum (Fastball, Relievers, 400+ Pitches)
Pitcher InSwStr OutSwStr Diff 1-0 Zone% 2-0 Zone% 3-0 Zone%
Ken Waldichuk 10.2% 8.1% 2.1 41.2% 56.7% 25.0%
Shintaro Fujinami 15.9% 6.7% 9.2 51.6% 55.1% 57.9%
Phil Bickford 17.3% 12.0% 5.3 52.0% 44.1% 44.4%
Reynaldo López 18.1% 9.9% 8.2 50.9% 57.1% 62.5%
Chris Flexen 플렉센 10.6% 5.8% 4.8 48.6% 36.4% 33.3%
Félix Bautista 22.0% 17.0% 5.0 52.5% 50.0% 60.0%
Zack Thompson 10.4% 8.3% 2.1 52.3% 31.3% 55.6%
Tanner Scott 21.1% 8.3% 12.8 45.1% 52.9% 30.8%
Drew Smith 15.4% 8.1% 7.3 51.9% 55.3% 36.4%
Jake Diekman 13.2% 7.8% 5.4 53.6% 44.2% 61.1%
Julian Merryweather 11.8% 7.6% 4.2 53.8% 56.4% 20.0%
Trevor Richards 12.3% 6.8% 5.5 51.0% 44.4% 50.0%
Alexis Díaz 20.6% 4.7% 15.9 49.6% 52.4% 46.7%
Alec Marsh 12.6% 9.5% 3.1 49.3% 44.0% 50.0%
Bryan Abreu 23.0% 8.3% 14.7 53.2% 51.1% 61.1%
Matt Brash 14.2% 8.5% 5.7 48.7% 52.2% 60.0%
Ron Marinaccio 17.4% 11.0% 6.4 53.4% 53.6% 66.7%
Nate Pearson 14.9% 10.2% 4.7 50.6% 53.1% 55.6%
Averages           –           –          – 54.0% 59.2% 66.7%

Can Shintaro Fujinami find the zone? I don’t know. I’m sure he’ll try and I hope he does. His stuff looks electric. Some pitchers can be effectively wild, but Fujinami cannot. Some of the pitchers on this list are excellent pitchers and shouldn’t tweak anything, while others may benefit from more in zone fastballs.





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LightenUpFGmember
1 month ago

Red Sox will sign this guy and count it as progress. At least his wind up will be fun to watch… the home runs, not so much.