MLB Daily DeltaWeek 20 · August 6, 2026
Cionel Pérez
NYM · P
Change to
Portrait of Mark Leiter Jr.
Mark Leiter Jr.
ATH · P
Change to
Who's more valuable, rest of season

Too close to call.

They split your categories 22, 1 even. Take whoever fills a bigger need.

Head-to-head
K
ERA
WHIP
W
SV

Cionel Pérez wins 2 (ERA, W); Mark Leiter Jr. wins 2 (K, SV); 1 even.

04

Under the hood

Underlying skill — each value vs league avg
Fastball Velolg 94.0 · higher = better
Cionel Pérez
96.9
Mark Leiter Jr.
92.2
Swinging-Strike %lg 11.0% · higher = better
Cionel Pérez
11.6%
Mark Leiter Jr.
14.0%
Strikeout %lg 22.0% · higher = better
Cionel Pérez
22.7%
Mark Leiter Jr.
26.4%
Chase %lg 28.5% · higher = better
Cionel Pérez
30.0%
Mark Leiter Jr.
33.8%
Hard-Hit % Allowedlg 40.0% · lower = better
Cionel Pérez
50.0%
Mark Leiter Jr.
31.9%
Barrel % Allowedlg 8.0% · lower = better
Cionel Pérez
12.9%
Mark Leiter Jr.
3.3%
xwOBA Allowedlg .315 · lower = better
Cionel Pérez
.346
Mark Leiter Jr.
.316
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
Cionel Pérez
2.856.67
lg xERA 4.10
now 5.82
3.70
Mark Leiter Jr.
2.856.67
lg xERA 4.10
now 5.47
3.72
WHIPlower is better
Cionel Pérez
1.101.73
now 1.59
1.24
Mark Leiter Jr.
1.101.73
now 1.46
1.24

Volume · rest of season
Strikeoutshigher is better
Cionel Pérez
4031.80
now 10
8
Mark Leiter Jr.
4031.80
now 25
15
Winshigher is better
Cionel Pérez
.0004.20
now 2
13
Mark Leiter Jr.
.0004.20
now 0
00
Saveshigher is better
Cionel Pérez
.0005.60
now 0
0
Mark Leiter Jr.
.0005.60
now 4
23
If you already own them — trade angle
Hold · wait & seeCionel Pérez — hold.conf 0.50
Hold · wait & seeMark Leiter Jr. — hold.conf 0.50
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