"Right now, there's not much to compare it to."
With every passing day, that changes.
Statcast™ debuted across Major League Baseball in 2015 and is capable of gathering previously immeasurable aspects of the game with high-resolution optical cameras along with radar equipment. That equipment precisely tracks the location and movements of the ball and every player on the field at any given time.
As a result, we don't have to be satisfied saying that Chris Carter hits the ball hard; we know the ball leaves his bat at 94.25 mph on average, tops among current Brewers hitters. We don't just know that Tyler Thornburg has a good curveball; we know he spins it at 2,718 revolutions per minute, 14th-best among Major League pitchers who have thrown the pitch at least 100 times, right behind Stephen Strasburg. And we don't just know that Jonathan Villar is fast; we know he reached 21.77 mph stealing third base in an April 28 game at Wrigley Field, the top speed for a Brewer on the bases this season.
But what do we know about Nelson?
Before a look at the Statcast™ data, here is the context: In 11 starts in April and May, Nelson owned a 2.82 ERA, a .686 opponents' OPS and more than twice as many strikeouts (59) as walks (28). Sixty-four percent of his pitches were strikes.
In three abbreviated starts in June -- small-sample alert -- Nelson has a 9.69 ERA, a 1.105 opponents' OPS and just as many strikeouts as walks (eight apiece). His strike rate is down to 56 percent.
According to Statcast™, Nelson is throwing more sinkers (46 percent in May to 52 percent in June) and they are being hit harder (89.2 mph average exit velocity in May to 93.8 mph in June). But his spin rate has remained stable, actually dropping ever so slightly from 2,205 revolutions per minute in May to 2,193 in June, which is good. A lower spin rate on a two-seam fastball generally means more ground balls.
Nelson is throwing fewer four-seam fastballs (23 percent in May to 18 percent in June), and the spin rate has decreased slightly, from 2,382 rpm in April to 2,350 in May to 2,296 in June. On four-seam fastballs, spin is generally good, generating more swings and misses.
Here's the most contrary piece of information: Nelson's slider may be the best it's been all year. Its velocity is down slightly, to 86.4 mph, offsetting a similar dip on his four-seam fastball, and the spin rate is up, from 2,128 rpm in May to 2,351 in June. Statcast™ has recorded 36 Nelson sliders in his three June starts, none of which were put in play.
The spin rates are intriguing to Nelson.
"The thing I think is pretty cool is that different spin rates can make the ball do different things," Nelson said. "You would think a sinker is spinning more than a four-seam fastball, because [the sinker] is actually moving. But it's actually spinning way less. The same thing with a curveball versus a slider.
"I find that stuff interesting. But here's the thing: You can give us numbers, but there's still not a proven way to get the result you want. Showing those numbers is showing the end conclusion. It's not showing the process. For us, whether you're a pitcher or a position player, you're more interested in the process."
The process is up to pitching coach Derek Johnson, who is in his first year on the job. He is the conduit between the Brewers' growing research and development team, and players like Nelson.
"We try to use every piece of information to understand performance. That includes scouting information, coaching-staff observations, and when possible, more specified information from sources like Trackman or Statcast™," Brewers general manager David Stearns said. "The key, of course, is that we discuss any relevant findings with our coaches. Ultimately, they're the ones that decide what information is best shared with players and what information is best kept out of their minds."
In Nelson's last outing in San Francisco, he was charged with eight runs (six earned) on eight hits, but the Brewers committed all four of their errors with Nelson on the mound, including one charged to Nelson himself.
"It wasn't like it was gapper after gapper," Nelson said.
He will work opposite A's right-hander Sonny Gray on Tuesday, with first pitch scheduled for 9:05 p.m. CT.