MLB Daily DeltaWeek 18 · July 27, 2026
Portrait of Michael Petersen
Michael Petersen
MIA · P
Change to
Portrait of Ryan Zeferjahn
Ryan Zeferjahn
LAA · P
Change to
Who's more valuable, rest of season

Ryan Zeferjahn.

He projects to help you in more roto categories the rest of the way — strikeouts and ERA.

Head-to-head
K
ERA
WHIP
W
SV

Ryan Zeferjahn wins 2 categories (K, ERA); Michael Petersen wins 1 (WHIP); 2 even.

04

Under the hood

Underlying skill — each value vs league avg
Fastball Velolg 94.0 · higher = better
Michael Petersen
97.7
Ryan Zeferjahn
97.4
Swinging-Strike %lg 11.0% · higher = better
Michael Petersen
14.1%
Ryan Zeferjahn
13.7%
Strikeout %lg 22.0% · higher = better
Michael Petersen
29.1%
Ryan Zeferjahn
32.4%
Chase %lg 28.5% · higher = better
Michael Petersen
31.8%
Ryan Zeferjahn
23.4%
Hard-Hit % Allowedlg 40.0% · lower = better
Michael Petersen
43.3%
Ryan Zeferjahn
34.0%
Barrel % Allowedlg 8.0% · lower = better
Michael Petersen
11.5%
Ryan Zeferjahn
6.0%
xwOBA Allowedlg .315 · lower = better
Michael Petersen
.286
Ryan Zeferjahn
.273
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
Michael Petersen
2.026.80
lg xERA 4.10
now 3.63
3.69
Ryan Zeferjahn
2.026.80
lg xERA 4.10
now 5.74
3.08
WHIPlower is better
Michael Petersen
1.011.50
now 1.12
1.24
Ryan Zeferjahn
1.011.50
now 1.39
1.36

Volume · rest of season
Strikeoutshigher is better
Michael Petersen
4038.40
now 23
16
Ryan Zeferjahn
4038.40
now 32
22
Winshigher is better
Michael Petersen
.0002.80
now 1
01
Ryan Zeferjahn
.0002.80
now 2
12
Saveshigher is better
Michael Petersen
.0002.40
now 1
01
Ryan Zeferjahn
.0002.40
now 1
01
If you already own them — trade angle
Sell HighMichael Petersen — sell high. His value is peaking; good time to trade him.conf 0.76
BuyRyan Zeferjahn — buy.conf 0.91
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