MLB Daily DeltaWeek 25 · September 10, 2026
Engraved portrait of Kumar Rocker
week 25
this weekSELL
last weekHOLD

Kumar Rocker

TEX·P
data as of September 10, 2026·week 25
flipped from HOLD on September 10, 2026
Sell stable xERA 4.59 +0.49 vs league with no luck excuse; move on.med 0.70
ROSK 9ERA 4.42WHIP 1.39W 0–1SV 0

Rocker is a sell — his expected ERA sits a half-run above league.

His expected ERA is 4.59 in a sample of 593 batters, well past the point where that number becomes reliable, and it is nearly half a run above the league average of 4.10. The trend is the wrong direction: his expected ERA has stepped up across the season rather than settling down. His expected wOBA allowed is .329, also above league average, and there is no luck story to soften either number. His strikeout rate of 21.4% is essentially league average and his walk rate of 9.3% is above it. Nothing in the profile says the true skill is better than the surface line. This is the level he is at. Sell. 9 K and a 4.42 ERA ROS is waiver-wire filler — a drop, not a stash.

VS His Norm

  • Strikeout %21.4%—+1.8% ▲vs his ~19.6% career norm
  • Walk %9.3%—+0.0% ▲vs his ~9.3% career norm

Drivers

  • xeraSIGNALstable xERA 4.59 +0.49 vs league with no luck excuse
metric · nowrolling trajectoryvs. leaguestabilized?
Hard-Hit % Allowed39.8%
39.8%*
lg avg 40.0% ▼−0.2%vs his norm —
407 / 50 BBE
Barrel % Allowed7.6%
7.6%*
lg avg 8.0% ▼−0.4%vs his norm —
407 / 60 BBE
xwOBA Allowed.329
believable since May 25.329*
lg avg .315 ▲+.014vs his norm —
593 / 200 TBF
xERA4.59
4.59*
lg avg 4.10 ▲+0.49vs his norm —
593 / 200 TBF
ERA4.61
4.61*
lg avg 4.10 ▲+0.51vs his norm —ERA is above the ~4.10 league average — expect it to fall.
134.7 / 200 IP
Strikeout %21.4%
norm21.4%*
lg avg 22.0% ▼−0.6%vs his norm +1.8% ▲
593 / 70 TBF
Walk %9.3%
norm9.3%*
lg avg 8.0% ▲+1.3%vs his norm +0.0% ▲
593 / 170 TBF
BABIP Against.307
.307*
lg avg .295 ▲+.012vs his norm —BABIP Against is above the ~.295 league average — expect it to fall.
407 / 800 BIP
Swinging-Strike %12.4%
12.4%*
lg avg 11.0% ▲+1.4%vs his norm —
593 / 60 TBF
Chase %31.1%
31.1%*
lg avg 28.5% ▲+2.6%vs his norm —
593 / 60 TBF
Fastball Velo94.5 mph
94.5 mph*
lg avg 94.0 mph ▲+0.5 mphvs his norm —
2281 / 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% 21.4%→20.9%signal9 K — K% 21.4% (signal) tempered to career ~19.6% → projected 20.9% over ~12 remaining IP.
xERA 4.59signal4.42 ERA — xERA 4.59 (signal) blended 65% skill / 35% league 4.10 at 56 IP.
BB% 9.3% + contactsignal1.39 WHIP — a 9% walk rate plus BABIP-against 0.301 gives a 1.43 skill WHIP, blended 65…
run support + role0-1 W — wins ride run support and how deep he goes, not just skill.
role (starter)0 SV — role: starter, not in the save mix.
rosterdrop9 K ROS, 4.42 ERA

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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