Sarris: Which pitchers are showing better things this spring – and should we care?

Spring training numbers don’t matter, according to conventional wisdom. These players are not Really try, and most of the time, teams don’t field rosters that are consistently full of major league talent.

That can’t be entirely true, however.

For one thing, major league teams make decisions based on spring training — there are literally positional battles going on at almost every club. Most of the time, it’s for one of the bottom spots on the roster, but that means teams are actually looking at a set of numbers to make decisions.

Then there’s real evidence that those numbers matter, that the spring numbers are (slightly!) predictive of regular season performance. They are, after all, a month’s worth of games. There’s probably a signal in there, as Dan Rosenheck of The Economist once found. Others have found that quickly stabilizing process stats contain a certain signal – things like strikeout rate and ground ball rate can quickly tell us something about the changes from season to season that a player can suffer.

One way to try to extract as much signal as possible from the noise is to focus on process statistics like these. We have one here for pitchers: Stuff+ only looks at the physical properties of a pitch and stabilizes very quickly. For four-seam fastballs, for example, we start getting more signal than noise after just 18 fastballs thrown.

There are still extenuating circumstances. Starting pitchers who pitch for three innings are not the same as starting pitchers who pitch for six innings, that’s true.

But we do know that the translation from reliever to starting pitcher has been in the range of five points from Stuff+. So if we just focus on rookie pitchers who threw a decent cross section of pitches in front of the machines this spring and increased their Stuff+ by more than five points, we should be able to find some real change under the hood. Let’s rank the best players and highlight a few that stand out.

Number one is fun, but there might be a few pitchers ahead of him in line for this Tampa rotation. Still, for Taj Bradley’s long-term value, it’s great to see his Stuff+ lining up with minor league scouting reports. Connor Gray has made some progress, but looks like a deep room in New York, especially if we have to subtract a few points from Stuff+ once he hits 80 slots per spawn. The same could be said of Matthew Liberatore, who will likely be needed in St. Louis. But once we subtract the reliever penalty, it falls below the 97+ trick average for beginners.

Ryan Feltner might have better things once out of altitude, but the reality remains that for now, at least, he has to get back there. (In related news, we’re considering tuning the Altitude Stuff+.) Opening Day starter Mitch Keller got some love here a while ago, as did Kyle Bradish here. Things look good for these picks.

Here are the other entries that caught my attention the most. Feel free to check out the Stuff+ spring numbers (and numbers by location) as well as the WBC numbers in the Google doc here.

Already a Stuff+ darling, Rasmussen has pushed even where he was last year. Much of it worked on refining its two sliders. Well, okay, one of them is a cutter on the sheet, but it’s really what’s called a “gyro” slider, a powerful, low-movement slider.

“There’s only one slider button on the PitchCom,” Rasmussen told me last week. “We call it a cutter. This is my old slider, and we took some depth out of it so I could throw it harder.

It also doesn’t look like a cutter.

What this power slider does is give Rasmussen another pitch he can throw to get a called strike, just like he did here. A whopping 65% of the “cutters” he has thrown this spring have been either a foul, swing or call hit. Where the sweeper has larger platoon divisions and is sometimes harder to corral, this step is all about power and command. A bit like a cutter?

Stuff+ is important, but efficiency is also important for a starter on the Rays, who averaged just over 80 pitches per start last year.

“When you know you’ve got a tough enough cap, you better throw it over the plate,” he laughed.

Rasmussen peaked at around 90 pitches in early August and early September, and if he really can master that broken three-ball approach, he may still be valuable in any format despite his lack of depth in the matches. He won 11 games last season after all and had 18 decisions despite his lack of length.

“I don’t know why he hasn’t had better results,” an analyst once told me about Pivetta. “Our trick numbers love it.”

Well, this one too. And it was his four-seam fastball — his other throws last year rated about average or worse by Stuff+ — this spring his breaking balls both seem more by that stat.

For its curve, it’s all about the bike. He’s throwing it four mph harder this spring, and even if it drops a tick or two, it’ll be a lot harder than his 77 mph curveball last year. That extra zip cost a bit of movement (about three or four inches of drop) but Stuff+ likes the change.

On the side of the slider, it just added drop to the terrain. Three inches drop. It now looks like this:

He hasn’t mastered the pitch surprisingly well – six out of 14 shots thrown, with only one allowed – and that’s been part of the problem in the past. But maybe it will be easier to command than his curveball. Less movement is usually easier to command, at least.

The Red Sox need Pivetta, and his business seems to be stepping up this spring. Could he finally implement an under-four ERA and reduce the home run rate by improving that side of the ledger? His pitches remain below average, and maybe they won’t improve, so this is the best way for him.

We already loved Luis Ortiz because of his Stuff+, and now he’s pushing it to new heights. He already has the big fastball and the power curve slider thing, but this spring even his change is rated above average by Stuff+. And his slider went from good (119 Stuff+ last year) to elite (142 Stuff+ this spring) adding another inch and a half of drop over his fastball (since his fastball also added some carry ). We have to take a look.

88 mph and off the table. Bad.

But can he push someone out of the rotation? He threw 45 pitches last time out with the Pirates and was holding serve with other stretch starters. But now he’s with the WBC, where he’s thrown 23 more pitches and has the third-highest Stuff+ in the tournament, but that’s not going to help his volume. Roansy Contreras’ business is down a bit, but he needs to get a legit shot if there’s no injury. Rich Hill is still there throwing curveballs. Vince Velasquez is three innings and should get the first shot at the fifth tee. Johan Oviedo’s average and general forfeit continued, and he threw 41 pitches in his last outing.

There’s a person or two between Ortiz and a rotation location in Pittsburgh. Stay alert.

Beautiful Briske, Tigers

Owner of the second highest speed jump in spring training so far, Beau Briske also has the fewest shots per appearance in this sample. So maybe make his jump into fastball Stuff+ — from 96 Stuff+ last year to 121 this spring — with a grain of salt. Maybe he’ll drop more than five points if the Tigers push his shots per appearance.

Or maybe even though we were looking for starting pitchers here, we found a sleeper in the Tigers bullpen. In his last outing, Brieske threw 10 fastballs and had a Stuff+ on 140 on it. It has alternated being better with change and slider, but overall both look like real weapons too.

The Tigers are going to need someone to get behind Alex Lange in the bullpen, and they could have their Beau.

It’s not fastball with Baumann this spring (last year his fastball was his best shot per Stuff+). Only the lightly pitched change was above average by Stuff+, and it came in such a small sample (on such tricky ground) that it’s probably more informative to say the change only had a whiff only three percent of the time it was launched. So in a way, Baumann was a one-pitch guy on a team that was starting to get crowded in the rotation.

Well, the Orioles acquired two more starters this offseason, and Grayson Rodriguez looks ready, but Baumann’s arsenal has taken a leap forward, with both his slider (118 Stuff+) and his curve (112 Stuff+) well above average now.

The slider also has a two-inch drop and two-inch horizontal movement. It passes the eyesight test, with a firm 90 mph motion and two shots:

A slightly firmer curve (+1 mph) can get back to where it was, but a little more run on the fastball and more movement on the slider made Baumann a legit three-pitch pitcher. And all of those numbers held up even as Baumann pushed his pitches per appearance to over 50.

What place will he finally have? FanGraphs doesn’t even have him in the club’s top 10 starters OR relievers right now, so he has some catching up to do. But Tyler Wells lost some stuff this spring, and if the team decides they want to take a look at Baumann while sending Rodriguez, it wouldn’t be an impossible outcome. Or Baumann is what Keegan Akin was last year, a multi-inning bridge down the middle. Looks like he’s upped his thing and yet should have some role.

(Pivetta top photo: Winslow Townson/Getty Images)