Arrighetti: Spaghetti with No More Meatballs

After a tale of two halves, what can we expect from Arrighetti

Editor’s note: This article was written before Arrighetti’s spectacular one run outing against the Mets last Saturday.

Over the years, I always find the gut reactions to projections to be intriguing. Often, removing the bias and taking a purely statistical approach to trying to predict the future performance of a player. There are things such as injuries that can skew the numbers significantly, but every year projections get better – but still draw the ire of fans when the projections don’t align with their views. With “7” projection systems listed on Fangraphs today, different methodologies are applied, each with their own pros and cons.

Arrighetti projects in a range of 133-145 IP of 4.11-4.41 ERA baseball, giving him a range of 1.2-1.9 WAR. Solid numbers that follow pretty closely to his 145 IP of 4.53 ERA baseball and 1.6 WAR last season.

Personally, I think this will be Spencer’s break-out year, going from a solid but unspectacular pitcher to something truly special. I don’t necessarily think that the projections are unfair given not only his performance last year, but the previous ~450 innings similarly produced a low-mid 4 ERA across his minor league tenure.

So other than gut feel and personal bias, why am I so high on Spencer?

There’s a few answers. You could simply argue that Spencer was called up before he was ready due to injuries last year. Or the easiest answer is looking at his splits, which show a tale of 2 halves – 80 IP of 5.63 ERA baseball in the first half of the year compared to the second producing 65 IP of 3.18 ERA. This of course is a great indicator, but not my primary reasoning.

For those who haven’t read either of Fangraphs articles on him – both the initial about him being all in on pitching analytics and the second about his evolution with his experience in the majors, I highly recommend them. For a quick summary, Arrighetti has demonstrated a remarkable understanding and passion for the analytics behind pitching, understanding seam-shifted wake, vertical approach angles, and understanding a lot of the science behind the modern revolution in pitching ushered in during the Luhnow/Strom era. In their more recent article about his evolution, he discusses some of the negative impacts on focusing on elements of the pitch design – maximizing the Stuff+ of the pitch, but in doing so losing some elements of deception and ability to trick batters into believing off-speed pitches were fastballs.

https://baseballsavant.mlb.com/savant-player/spencer-arrighetti-681293?stats=statcast-r-pitching-mlb

As you take a look at Spencer’s baseballsavant page, it’s an intriguing mix. From xERA being half a run lower at 4.05, to possessing elite breaking pitches with high whiff/k rates, you can see the start of some of the intriguing components that point to a potential break-out, particularly when paired with the Astros analytics.

Baseball Savant has 7 pitches listed for Spencer, although with just 10 Sinkers and 3 Sliders, they could be misclassified, experiments, or used as unexpected freeze pitches – but more importantly, simply lack the data to draw meaningful conclusions on.

https://baseballsavant.mlb.com/savant-player/spencer-arrighetti-681293?stats=statcast-r-pitching-mlb

As you look at the data, the thing that immediately pops out, is that Spencer’s breaking stuff was absolutely dominant, while his fastball was absolutely dominated by batters. In particular when thrown lower in the zone. Now, having the pitch that you throw the most (40.6% 4-Seamers) get crushed to the tune of .367 xWOBA with a poor whiff rate is not a great sign, but allows for “easy” adjustments to his arsenal – both in usage, and effectiveness.

Enter the introduction of Arrighetti’s new 2-Seam fastball. Arrighetti’s velocity is about league average, but his unique arm angle, release point as well as the elite extension on his pitches, allow for his velocity to play up, with pitches “getting on batters” faster than anticipated. I expect that the modified fastball approach – including usage of a 2-seamer will allow Spencer to make the most of the extension and release point.

If Spencer is able to take his fastball from one of the worst in the league to even close to league average, he changes from a remarkable strike-out pitcher to having the potential to be one of the elite starters in the league.

While I’m usually less than sold on the player “in the best shape of their career”, or “modifying their swing”, or “adding a pitch” type of stories that come out of Spring Training every year – I foresee some simple modifications in usage of pitches, and making the most of Spencer’s delivery offering a potential for him to take it to a whole new level.

Additionally, having just turned 25, there is reason to believe Spencer will naturally progress as he gets closer to the peak seasons of his career.

With all of this said, my gut reaction is that he will outperform his projections and expectations by a large margin and become one of the surprises of the season. My guess is we will likely see a drop in strike-out rate, but drastically improved performance as batters have weaker contact against fastballs earlier in the count, but the ability to utilize his breaking pitches more often as needed for their devastating strike-out ability.

My completely unscientific, and fully biased belief is that Arrighetti not only earns his first All-Star appearance this year, but pitches to the tune of a low 3’s ERA, more than doubling his WAR, and earning him some Cy Young votes if he is able to stay healthy for the entire year.

What would your projection be for Arrighetti this year?