MLB Daily DeltaWeek 18 · July 29, 2026
week 18
this weekHOLD
last weekHOLD

Isaac Mattson

data as of July 29, 2026·week 18
Hold · wait & see skill near league average (6.16); hold and wait — key skill metric not yet stable enough to call.med 0.50 (narrative held for review)
ROSK 13ERA 3.70WHIP 1.24W 0–0SV 0

Mattson is a hold — limited data, nothing to trust yet.

ROS projects K 15 YTD → 13 ROS. Stable, rosterable; no clear edge to exploit either way.

VS His Norm

  • Strikeout %20.4%−0.5%vs his ~20.9% career norm

Drivers

  • xeraNOISEskill near league average (6.16)
metric · nowrolling trajectoryvs. leaguestabilized?
Hard-Hit % Allowed48.5%
48.5%*
lg avg 40.0% +8.5%vs his norm —
101 / 50 BBE
Barrel % Allowed11.9%
11.9%*
lg avg 8.0% +3.9%vs his norm —
101 / 60 BBE
xwOBA Allowed.373
.373*
lg avg .315 +.058vs his norm —xwOBA Allowed is above the ~.315 league averageexpect it to fall.
147 / 200 TBF
xERA6.16
6.16*
lg avg 4.10 +2.06vs his norm —xERA is above the ~4.10 league averageexpect it to fall.
147 / 200 TBF
ERA4.91
4.91*
lg avg 4.10 +0.81vs his norm —ERA is above the ~4.10 league averageexpect it to fall.
33 / 200 IP
Strikeout %20.4%
norm20.4%*
lg avg 22.0% −1.6%vs his norm −0.5%
147 / 70 TBF
Walk %10.2%
norm10.2%*
lg avg 8.0% +2.2%vs his norm −1.6% Walk % is below his ~11.8% normexpect it to rise.
147 / 170 TBF
BABIP Against.327
.327*
lg avg .295 +.032vs his norm —BABIP Against is above the ~.295 league averageexpect it to fall.
101 / 800 BIP
Swinging-Strike %10.5%
10.5%*
lg avg 11.0% −0.5%vs his norm —
147 / 60 TBF
Chase %26.3%
26.3%*
lg avg 28.5% −2.2%vs his norm —
147 / 60 TBF
Fastball Velo94.1 mph
94.1 mph*
lg avg 94.0 mph +0.1 mphvs his norm —
609 / 50 PITCHES

5×5 ROS Outlook

rest of season

Where each category goes the rest of the way, and the skill that drives it. Tap a row to expand the full derivation.

statytdrosdriverconf
K% 20.4%→20.7%signal13 K — K% 20.4% (signal) held to career ~20.9% → projected 20.7% over ~17 remaining IP.
xERA 6.16noise3.70 ERA — xERA 6.16 (noise) blended 0% skill / 100% league 3.70 at 20 IP.
BB% 10.2% + contactnoise1.24 WHIP — a 10% walk rate plus BABIP-against 0.299 gives a 1.48 skill WHIP, blended 0…
run support + role0-0 W — wins ride run support and how deep he goes, not just skill.
role (setup)0 SV — role: setup, not in the save mix.
rosterdeep3.70 ERA, 1.24 WHIP

Every projection traces to a sabermetric input. The driver and confidence shown per row are always visible; tap any row to expand the full derivation.

Tweet
Compare with

Comparisons

head-to-head matchups