MLB Daily DeltaWeek 18 · July 29, 2026
Isaac Mattson
PIT · P
Change to
Portrait of JoJo Romero
JoJo Romero
STL · P
Change to
Who's more valuable, rest of season

Isaac Mattson.

He projects to help you in more roto categories the rest of the way — ERA and WHIP. JoJo Romero’s box score looks better right now, but the luck-stripped projection flips it.

Head-to-head
K
ERA
WHIP
W
SV n/a

Isaac Mattson wins 2 categories (ERA, WHIP); JoJo Romero wins 1 (K); 1 even; SV n/a.

04

Under the hood

Underlying skill — each value vs league avg
Fastball Velolg 94.0 · higher = better
Isaac Mattson
94.1
JoJo Romero
94.5
Swinging-Strike %lg 11.0% · higher = better
Isaac Mattson
10.5%
JoJo Romero
9.4%
Strikeout %lg 22.0% · higher = better
Isaac Mattson
20.4%
JoJo Romero
23.1%
Chase %lg 28.5% · higher = better
Isaac Mattson
26.3%
JoJo Romero
27.9%
Hard-Hit % Allowedlg 40.0% · lower = better
Isaac Mattson
48.5%
JoJo Romero
43.1%
Barrel % Allowedlg 8.0% · lower = better
Isaac Mattson
11.9%
JoJo Romero
8.1%
xwOBA Allowedlg .315 · lower = better
Isaac Mattson
.373
JoJo Romero
.337
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
Isaac Mattson
2.134.69
lg xERA 4.10
now 4.12
3.70
JoJo Romero
2.134.69
lg xERA 4.10
now 2.70
3.77
WHIPlower is better
Isaac Mattson
1.041.59
now 1.47
1.24
JoJo Romero
1.041.59
now 1.16
1.25

Volume · rest of season
Strikeoutshigher is better
Isaac Mattson
4030.60
now 15
13
JoJo Romero
4030.60
now 25
17
Winshigher is better
Isaac Mattson
.000.480
now 0
00
JoJo Romero
.000.480
now 0
00

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

If you already own them — trade angle
Hold · wait & seeIsaac Mattson — hold.conf 0.50
Hold · wait & seeJoJo Romero — hold.conf 0.50
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