MLB Daily DeltaWeek 31 · October 26, 2026
week 31
this weekBUY-LOW
last weekBUY-LOW

Geoff Hartlieb

ATH·P
data as of October 26, 2026·week 31
Buy Low fastball velocity stable and above league, the arm is fine — luck-free xERA 3.92 sits 0.18 below league, a real arm the ERA is hiding; BABIP-against 0.337 elevated and unstable, bloating the ERA; buy the player, not the number.high 0.87
ROSK 0ERA 3.70WHIP 1.24W 0–0SV 0

Hartlieb is a buy-low — his ERA is BABIP noise, not the arm

His BABIP-against is .337, 42 points above the league average of .295. BABIP-against needs around 800 balls in play to be reliable and he has 87, so that gap is luck, not a read on his stuff. Strip it out and his expected ERA is 3.92, .18 below league average — better than the 4.82 the box score shows. The velo backs that up: 95.3 mph on the fastball, above the 94.0 league mark, and climbing across the sample. His barrel rate allowed is 5.7% against an 8.0% league average. He does not miss bats at a high clip — 17.7% strikeouts — but the swinging strike and chase rates say the strikeout number has room to rise. The surface is worse than the pitcher. Buy low. Deep-league buy low: the 3.70 ERA / 1.24 WHIP projection is a stash-worthy asset, not a drag.

VS His Norm

  • Strikeout %17.7%—−1.9% ▼vs his ~19.6% career norm

Drivers

  • xeraNOISEluck-free xERA 3.92 sits 0.18 below league — a real arm the ERA is hiding
  • babip_againstNOISEBABIP-against 0.337 elevated and unstable — bloating the ERA
  • p_fastball_veloSIGNALfastball velocity stable and above league — the arm is fine
metric · nowrolling trajectoryvs. leaguestabilized?
Hard-Hit % Allowed43.7%
43.7%*
lg avg 40.0% ▲+3.7%vs his norm —
87 / 50 BBE
Barrel % Allowed5.7%
5.7%*
lg avg 8.0% ▼−2.3%vs his norm —
87 / 60 BBE
xwOBA Allowed.305
.305*
lg avg .315 ▼−.010vs his norm —xwOBA Allowed is below the ~.315 league average — expect it to rise.
124 / 200 TBF
xERA3.92
3.92*
lg avg 4.10 ▼−0.18vs his norm —xERA is below the ~4.10 league average — expect it to rise.
124 / 200 TBF
ERA4.82
4.82*
lg avg 4.10 ▲+0.72vs his norm —ERA is above the ~4.10 league average — expect it to fall.
28 / 200 IP
Strikeout %17.7%
norm17.7%*
lg avg 22.0% ▼−4.3%vs his norm −1.9% ▼
124 / 70 TBF
Walk %11.3%
norm11.3%*
lg avg 8.0% ▲+3.3%vs his norm −3.5% ▼Walk % is below his ~14.8% norm — expect it to rise.
124 / 170 TBF
BABIP Against.337
.337*
lg avg .295 ▲+.042vs his norm —BABIP Against is above the ~.295 league average — expect it to fall.
87 / 800 BIP
Swinging-Strike %13.3%
13.3%*
lg avg 11.0% ▲+2.3%vs his norm —
124 / 60 TBF
Chase %34.2%
34.2%*
lg avg 28.5% ▲+5.7%vs his norm —
124 / 60 TBF
Fastball Velo95.3 mph
95.3 mph*
lg avg 94.0 mph ▲+1.3 mphvs his norm —
435 / 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% 17.7%→18.9%signal0 K — K% 17.7% (signal) lifted to career ~19.6% → projected 18.9% over ~0 remaining IP.
xERA 3.92noise3.70 ERA — xERA 3.92 (noise) blended 0% skill / 100% league 3.70 at 3 IP.
BB% 11.3% + contactnoise1.24 WHIP — a 11% walk rate plus BABIP-against 0.300 gives a 1.59 skill WHIP, blended 0…
run support + role0-0 W — wins ride run support and how deep he goes, not just skill.
role (middle)0 SV — role: middle, 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.

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