J.B. Bukauskas and the RPM Revolution

Written by: Dylan Matthews (@dmattprospects)

Follow us on Twitter! @Prospects365

Analytically, everyone in baseball is striving to keep up with the Astros. Their pitchers dominate baseball with high strikeout numbers at every level! Why is that? Their answer is that they attack batters in ways that used to be considered pitcher suicide: They attack the top of the strike zone with fastballs that have high rotations per minute (RPM) and good velocity.

Nowadays, hitters train to hit low pitches in the air, leading to less outs induced by the low, straight and hard fastball. The Astros stopped throwing it into a batter’s natural swing path so often, instead opting to challenge hitters up in the zone with high-spin rate fastballs.

The unfortunate thing about trying to find these high-spin rate pitchers at the minor league level is that many of the MiLB parks are not yet equipped to configure this data. For prospects, this data is being pulled from key events like the Arizona Fall League and the Future Stars game.

Obviously no one cares about RPM if you’re consistently not getting outs, so let’s take a look at my favorite pitcher that is not an industry-wide top one hundred prospect: J.B. Bukauskas.

J.B. Bukauskas

2018 Stat line: 2.14 ERA, 59 IP, 71 K, 1.12 WHIP, 10.83 K/9

Grades: FB- 65, SL- 65, CH- 50, CNTRL- 50

The constant fear of owning a minor league pitcher who could be destined for the bullpen is a real thing. Unfortunately, the arms destined for the pen usually have some of the best stuff in the minors, but failure to harness a third pitch or commanding the strike zone proves too difficult a feat to overcome. At some point, you have to look at the body of work and call it what it is: J.B. Bukauskas is nasty! Just take a look at this:

From the Arizona Fall League: Top spin rates (four-seam fastball; in rpm)

2,872 — Darwinzon Hernandez, Red Sox

2,841 — J.B. Bukauskas, Astros

2,823 — J.B. Bukauskas, Astros

2,804 — J.B. Bukauskas, Astros

2,801 — J.B. Bukauskas, Astros

2,775 — J.B. Bukauskas, Astros

2,769 — J.B. Bukauskas, Astros

2,766 — J.B. Bukauskas, Astros

2,763 — Jesus Tinoco, Rockies

2,769 — J.B. Bukauskas, Astros

In case you didn’t notice, Bukauskas is on that list a lot! This shows that he consistently throws fastballs with high RPMs, which plays into his high strikeout numbers.

According to FiveThirtyEight: “When pitchers threw fastballs between 93 and 94 mph with an average spin range of 2,240 to 2,300 revolutions per minute, hitters posted a .279 average this season.” As pitchers exceeded said RPM, AVG steadily declined.

This chart below shows swing and miss percentage calculated from Driveline Research

spin rate

Now scroll back up to Bukauskas’s fastball spin rates from the AFL. Some of the right-hander’s RPMs are so high they don’t even register in the table above.

Why is it that fastballs spinning at these rates are so hard to hit? It’s because of the ball fighting the air against it. Another really cool image from the driveline article shows a ball fighting against the air.


If you’re interested in the science of why hitters struggle so much against the high spin rate fastballs, go give the article a read. If you give it a click, you’ll find a lot of fascinating studies that prove why high spin rate is effective. It even dives into the affects of lack of spin rate!

Bukauskas has been knocked by prospect evaluators for possessing a below average changeup, which often signals a path to the pen. In the Arizona Fall League, however, Bukauskas flashed a changeup that showed good depth and run away from left-handed batters, which is crucial for a starting pitcher attempting to make it through the order for a third time. The command is still a work in progress, but Bukauskas is an athlete with clean mechanics. I expect his stuff to continue to dominate opposing batters in the minors and anticipate a big league cup of coffee for him this summer. He doesn’t possess the huge arsenal that Forrest Whitley has, but I don’t see any reason why Bukauskas can’t be a strong SP2 in fantasy formats. Buy now if he’s available in your league, because his stock is going to skyrocket this season.

The last thing worth mentioning about Bukauskas is to not worry about his injury bug. This is the real reason why I think he is lower on prospect lists than he should be. The right-hander didn’t pitch much in 2017 professionally following a full season of college ball. Last season, his campaign was slowed drastically due to a back injury caused by a car accident. Pitchers with an injury history tend to be the ones worth avoiding, but it’s worth considering that none of the 22-year-old’s ailments have been arm related.

Bukauskas is currently my 48th-ranked prospect (my top-100 list can be found on my Twitter feed). I can’t recommend buying him enough, especially at his current price. With a ceiling of a top-end SP2 and the floor of a dominant, late inning reliever, Bukauskas will be lights out in 2019. Perhaps the best part will be the fact you acquired him before he officially explodes onto the prospect scene.

Follow P365 writer Dylan Matthews on Twitter! @dmattprospects

Follow us on Twitter! @Prospects365

Featured image courtesy of photographer Joseph Dwyer and MiLB.com

Leave a Reply