Does Sandy Alcantara have a fastball problem?

If you've watched him pitch in 2025, you don't need me telling you that Sandy Alcantara has been bad.

But for those just awakening from their slumber to Marlins baseball, here is a little refresher. Alcantara's 8.47 ERA ranks dead last out of the 103 MLB pitchers to already cross the 50-inning threshold this season, and he's on pace for the second-worst such season in Marlins history. In terms of bWAR, only Boston's Tanner Houck (-1.6) has proven a bigger on-field liability to his club on the mound than Alcantara (-1.5).

How can we explain the shocking demise of one of the greatest pitchers in Marlins history at age 29?

The low-hanging fruit is Tommy John surgery. Alcantara underwent the procedure shortly after the end of the 2023 season, one in which the Marlins surprised many en route to an 84-win playoff campaign. The two-time All-Star missed all of 2024 as a result. Although he looked sharp in spring training, there has not been a single consistently dominant outing from him since then.

Beyond that, there's been a subtle change to Alcantara's pitch selection that may be exacerbating the situation. 

The pitches in Alcantara's arsenal were distributed relatively evenly when he was at the peak of his powers in 2022. Here in 2025, his four-seam fastball, sinker and changeup are being used a similar proportion of the time, but he has cut the usage of his slider nearly in half, down to 12.8%. He's been featuring his curveball more often instead.

Adjusting pitch usage is not inherently a bad thing, but the results suggest another change would be more appropriate. Let's take a closer look at Alcantara's four-seamer. His usage of it compared to 2022 is nearly identical (up from 25.5% to 25.8%).

2022

2025

While never remarked as a strikeout pitcher—boasting a career 7.9 K/9 through 2023—Alcantara generated whiffs on 24.2% of four-seamers thrown in 2022. Here in 2025, hitters are whiffing just 14% of the time.

Take a close look at the pitch locations in the above graphics, you will notice that Alcantara previously placed a high percentage of his four-seamers at the very top of the strike zone or just above it. Too close to take and too inconvenient for hitters to reach with their "A-swing." 

When opponents did make contact with Alcantara's four-seamers, they would frequently get underneath them, as evidenced by an average launch angle of 25 degrees in 2022. That average has now come down to 17 degrees as he leaves more mistakes in the heart of the zone.

More concerningly, the average exit velocity against the pitch has ballooned from 91.1 mph to 96.8 mph. To put that in perspective, Shohei Ohtani's average EV is 96.0 mph. No pitcher's four-seamer (min. 50 PA) has resulted more frequently in hard hits (67.4% of the time). In 69 plate appearances ending on an Alcantara four-seamer, the league is hitting .345 with an Ohtani-esque .638 slugging percentage.

Alcantara is releasing the ball from a lower arm angle than ever. Perhaps that is part of this equation because it has changed the shape of his pitches—his four-seamer, for example, is drifting several more inches armside than it used to.

As far as a potential solution goes, why not tone down the usage of his four-seamer, using it more as a complement to his superior sinking two-seam fastball? Hitters collectively have a .267 average with a 0-degree launch angle off Sandy's sinker. It is reliably inducing ground balls for him, which ought to yield slightly better results moving forward with news that standout defender Otto Lopez is expected to see a majority of the reps at shortstop. 

The Marlins' hope of recouping substantial value for Alcantara at this year's trade deadline is rapidly fading. Their focus now should be pulling whatever levers they can to avoid one of the worst-pitched seasons in franchise history.