MLB Daily DeltaWeek 27 · September 27, 2026
week 27
this weekSELL-HIGH
last weekHOLD

Kenley Jansen

DET·P
data as of September 27, 2026·week 27
flipped from HOLD on September 27, 2026
Sell High BABIP-against 0.173 suppressed and unstable, flattering the ERA; luck-free xERA 3.60 is 0.40 above the ERA, regression coming; sell into the hype before regression.med 0.71
ROSK 0WHIP 1.24ERA 3.70W 0–0SV 0–0

Jansen is a sell-high — his ERA is built on a .173 BABIP

His ERA of 3.20 looks like the pitcher you would want, but the number keeping runs off the board is his BABIP-against: .173, against a league average of .295. BABIP-against needs around 800 balls in play to be reliable, and he has 105 — that gap is luck, not skill. His expected ERA is 3.60, 0.40 higher than what the box score shows, and that gap points to regression. He strikes out 28.3% of batters, above the league average of 22.0%, so there is real swing-and-miss skill, but he walks 12.8% of batters, well above the league average of 8.0%, and that free-pass rate is a persistent problem that the ERA is hiding. The surface is flattering him. Sell high.

VS His Norm

  • Strikeout %28.3%—−6.4% ▼vs his ~34.7% career norm
  • Walk %12.8%—+5.0% ▲vs his ~7.8% career norm

Drivers

  • babip_againstNOISEBABIP-against 0.173 suppressed and unstable — flattering the ERA
  • xeraNOISEluck-free xERA 3.60 is 0.40 above the ERA — regression coming
metric · nowrolling trajectoryvs. leaguestabilized?
Hard-Hit % Allowed38.1%
38.1%*
lg avg 40.0% ▼−1.9%vs his norm —
105 / 50 BBE
Barrel % Allowed9.5%
9.5%*
lg avg 8.0% ▲+1.5%vs his norm —
105 / 60 BBE
xwOBA Allowed.293
.293*
lg avg .315 ▼−.022vs his norm —xwOBA Allowed is below the ~.315 league average — expect it to rise.
180 / 200 TBF
xERA3.60
3.60*
lg avg 4.10 ▼−0.50vs his norm —xERA is below the ~4.10 league average — expect it to rise.
180 / 200 TBF
ERA3.20
3.20*
lg avg 4.10 ▼−0.90vs his norm —ERA is below the ~4.10 league average — expect it to rise.
45 / 200 IP
Strikeout %28.3%
norm28.3%*
lg avg 22.0% ▲+6.3%vs his norm −6.4% ▼
180 / 70 TBF
Walk %12.8%
norm12.8%*
lg avg 8.0% ▲+4.8%vs his norm +5.0% ▲
180 / 170 TBF
BABIP Against.173
.173*
lg avg .295 ▼−.122vs his norm —BABIP Against is below the ~.295 league average — expect it to rise.
105 / 800 BIP
Swinging-Strike %13.0%
13.0%*
lg avg 11.0% ▲+2.0%vs his norm —
180 / 60 TBF
Chase %30.1%
30.1%*
lg avg 28.5% ▲+1.6%vs his norm —
180 / 60 TBF
Fastball Velo93.9 mph
93.9 mph*
lg avg 94.0 mph ▼−0.1 mphvs his norm —
725 / 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% 28.3%→31.6%signal0 K — K% 28.3% (signal) lifted to career ~34.7% → projected 31.6% over ~0 remaining IP.
xERA 3.60noise3.70 ERA — xERA 3.60 (noise) blended 0% skill / 100% league 3.70 at 15 IP.
BB% 12.8% + contactsignal1.24 WHIP — a 13% walk rate plus BABIP-against 0.279 gives a 1.37 skill WHIP, blended 0…
run support + role0-0 W — wins ride run support and how deep he goes, not just skill.
role (closer)0-0 SV — role: closer.
rosterdeep7 SV, 3.70 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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