Atlanta Braves: Ian Anderson is working on slider, what he needs is a better fastball

Arizona Diamondbacks v Atlanta Braves
Arizona Diamondbacks v Atlanta Braves / Todd Kirkland/GettyImages

The Atlanta Braves are well underway in spring training and one of the more closely watched competitions in camp will be for the fifth spot in the Braves' rotation. With Michael Soroka currently dealing with hamstring tightness (the update we got today is that he did play catch today as a positive development), that competition has even more urgency. One guy that hopefully will factor into that competition in a positive sense is Ian Anderson.

Anderson pitched so poorly in 2022 that he ended up getting sent back down to the minors and frankly, he didn't look anything like a guy that you could trust in a big game anymore despite his track record of success in the postseason. The surface numbers were ugly: 5.00 ERA, 4.25 FIP, a career low 7.82 K/9, and a career high 4.35 walks per nine. If you can't miss bats, can't throw strikes when you need to, and get hit when to do throw it in the zone, that is not a good combination.

Observers have rightly noted that at this point, Ian is a two pitch pitcher with a fastball/changeup combo with his changeup being his best pitch (we'll get to the fastball shortly). Ian does have a curveball, but it was his least used pitch in 2022, doesn't have much in the way of movement or spin, and on a rate basis (based on run value which is a Statcast metric) it was Ian's worst pitch last season. That is why it was, at least at some level, heartening to see today that it looks like Ian is working on adding a slider to his arsenal.

Again, we haven't seen the pitch in action, so it is best not to draw to many conclusions since it sure doesn't sound like the slider is ready yet. However, what I want to talk about here is that a big limiting factor for Ian is the quality of his fastball and its characteristics that could continue to give him difficulties going forward.

Without spin, Ian Anderson's margin of error is small

Lets go ahead and get this out of the way: yes, we have seen Ian Anderson pitch well in the major leagues and no, he is not in anyway completely hopeless. In fact, one of the weirder things about this analysis is that in 2021, his four seem fastball was his best pitch by run value (-13 over 1,025 pitches thrown....negative is good here). He is incredibly talented and even if he doesn't ever learn to spin a baseball, if he can get his command back he can still find success.

However, it sure would be helpful if he could figure out how to unlock some spin rate because the numbers there are grim. The rough average spin of a four-seam fastball in MLB is around 2,300 RPM or so. The really good ones climb significantly higher, but that is the gist. What was Ian Anderson's spin rate in 2022 on his four-seam: 1937 RPM. That is shockingly low and, worse than that, it was a significant regression from his better, but still not great, 2045 RPM on the pitch in 2021. The result being less movement on the pitch, the complete inability to get that sort of rising action at the top of the zone that is so effective right now, and a flat fastball.

The end result being that by nearly every advanced metric you can measure pitch quality, Ian's four seam fastball was around 25%-30% worse than it was in 2021 and that was with iffy pitch characteristics to begin with. He saw big jumps against the pitch when it comes to wOBA, xWOBA, slugging, xSLG, batting average, xBA, and big drops in his whiff percentage and ability to put batters away with his fastball. For those wondering, the average velocity was roughly the same as his career average which is a shade over 94 MPH.

For Ian, it is a difficult fix

Fixing a fastball can be arguably the toughest thing to do. Sure, sometimes guys can retool their mechanics to be more efficient to add velocity and fiddle with grips to add some spin, but a lot of times you either have it or you don't. I am certain that the Braves are well aware that not only does Ian's spin rates on all of his pitches (his spin rate challenges extend elsewhere as well) rank low, but that he has been this way since his days in the minor leagues.

What will be curious to see in 2023 is if we see some significant changes here. Sure, if Ian has finely tuned command of all of his pitches, he can make it work without question. That is a really fine line to walk, though, especially for a guy that has struggled to maintain that consistency. A better breaking ball could certainly help the cause by changing eye levels in an at-bat and and giving hitters another offspeed option to respect other than his changeup. Maybe he can add a little velocity to his fastball somehow and take a little off his changeup to create some more separation between the two pitches to screw with hitters' timing and miss more bats that way.

One thing is for sure, Ian is going to need his fastball to be better (and hopefully with some more spin) in 2023 or else his chances of locking down a rotation spot in the big leagues are going to be a whole lot harder.