MLB Daily DeltaWeek 27 · September 27, 2026
Portrait of Aroldis Chapman
Aroldis Chapman
BOS · P
Change to
Portrait of Kevin Kelly
Kevin Kelly
TB · P
Change to
Who's more valuable, rest of season

Too close to call.

They split your categories 1–1, 2 even. Take whoever fills a bigger need.

Head-to-head
K
◀
ERA
WHIP
▶
W
SV n/a

Aroldis Chapman wins 1 (ERA); Kevin Kelly wins 1 (WHIP); 2 even; SV n/a.

04

Under the hood

Underlying skill — each value vs league avg
Fastball Velolg 94.0 · higher = better
Aroldis Chapman
96.9
Kevin Kelly
93.2
Swinging-Strike %lg 11.0% · higher = better
Aroldis Chapman
15.8%
Kevin Kelly
11.9%
Strikeout %lg 22.0% · higher = better
Aroldis Chapman
33.3%
Kevin Kelly
22.6%
Chase %lg 28.5% · higher = better
Aroldis Chapman
33.1%
Kevin Kelly
34.6%
Hard-Hit % Allowedlg 40.0% · lower = better
Aroldis Chapman
38.1%
Kevin Kelly
44.6%
Barrel % Allowedlg 8.0% · lower = better
Aroldis Chapman
6.8%
Kevin Kelly
5.9%
xwOBA Allowedlg .315 · lower = better
Aroldis Chapman
.252
Kevin Kelly
.284
stabilized — trust it · small sample yet · dashed = league avg · right = better
05

The tape

Rest-of-season projection · bold = leads
rest-of-season projection current season projection range
Rate · earned-run quality
ERAlower is better
Aroldis Chapman
24.53
lg xERA 4.10
now 0.48
2.64
Kevin Kelly
24.53
lg xERA 4.10
now 2.67
3.37
WHIPlower is better
Aroldis Chapman
.9001.43
now 0.86
1.25
Kevin Kelly
.9001.43
now 0.81
1.12

Volume · rest of season
Strikeoutshigher is better
Aroldis Chapman
4035
now 25
0
Kevin Kelly
4035
now 19
0
Winshigher is better
Aroldis Chapman
.0004.20
now 0
0–0
Kevin Kelly
.0004.20
now 3
0–0

SV — not applicable. Both pitch out of the rotation.

If you already own them — trade angle
BuyAroldis Chapman — buy.conf 0.92
Sell HighKevin Kelly — sell high. His value is peaking; good time to trade him.conf 0.95
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