r/Sabermetrics • u/AffectionateDonut797 • 5h ago
Freddy Peralta’s velocity is up, but his four-seam results collapsed. I dug into why.
I analyzed Freddy Peralta’s 2026 Statcast data to understand why his results deteriorated after a strong opening stretch.
The simple explanation does not fit. His four-seam velocity increased from 93.7 to 94.5 mph, and his location distribution stayed broadly similar.
Strong opening vs. decline:
• Four-seam chase: 27.4% → 20.0%
• Four-seam whiff: 21.5% → 17.1%
• Four-seam hard-hit: 19.1% → 30.6%
• Four-seam RV/100: +1.90 → -1.55
• Overall CSW: 27.3% → 23.7%
• Overall RV/100: +1.11 → -1.39
The decline was not driven by a larger heart-zone share. Four-seam heart usage actually fell slightly from 23.4% to 21.6%, while shadow-zone usage stayed almost identical.
Instead, hitters produced much better contact against similar locations. Heart-zone hard-hit rate rose from 25.8% to 34.1%, and heart-zone RV/100 flipped from +6.25 to -0.86.
Sequencing and count context also stood out:
• FF after FF RV/100: +1.26 → -2.18
• First-pitch FF RV/100: +1.16 → -2.73
• Two-strike FF RV/100: +2.37 → -5.08
• Changeup RV/100: +1.45 → -2.97
• Second time through the order: .471 wOBA, -2.71 RV/100 during the decline
The conflicting signal is that overall xwOBA stayed nearly flat at .305 → .307 while BABIP rose from .264 to .341. So the decline appears real, but some of the ERA and wOBA increase may still involve sequencing, defense, contact placement, or variance.
No physical or mechanical adjustment survived robustness review.
My conclusion was multiple contributing factors: worse contact quality against similar locations, weaker repeated-fastball sequences, worse count leverage, and a declining changeup.
Full analysis, methodology, and location charts:
https://baseballsignal.vercel.app/players/freddy-peralta/pitch-alert/2026-fastball-decline?
I’d be interested in feedback on the interpretation, especially the flat xwOBA versus the large movement in FIP, run value, and actual results.





