Head to head · 2026 pitching

Zack Kelly vs Angel Zerpa

In 2026 Zack Kelly has been worth 0.3 more wins. Both lines are computed from play-by-play on the same constants, so they are measured the same way rather than quoted from two sources.

Their 2025 seasons were among each other's nearest on rate statistics.

Zack Kelly BOS

Angel Zerpa MIL

2026 season

2026 pitching. The stronger figure in each row is highlighted — for ERA, FIP, WHIP and walks that is the lower one.
Statistic	Zack Kelly	Angel Zerpa
G	17	12
GS	0	0
IP	16.1	12.2
W	0	0
SO	14	8
ERA	3.31	6.39
FIP	3.65	5.31
WHIP	1.29	1.74
K/9	7.7	5.7
BB/9	3.9	4.3
FIP−	87	127
WAR	0.2	-0.1

Postseason

Box-score figures only: October is kept out of the season constants, so there is no wOBA, FIP or dbWAR for it.

Every published postseason, pitching, summed with the rates recomputed from the counts.
Statistic	Zack Kelly	Angel Zerpa
G	1	5
GS	0	0
IP	0.1	4.0
W	0	2
SV	0	0
SO	1	5
BB	0	3
ERA	0.00	2.25
WHIP	0.00	1.25
K/9	27.0	11.3
BB/9	0.0	6.8

Career

Totalled over the seasons published here, which is not the same as a whole career: a player who debuted before 2005 begins at 2005, not at his real first game.

Career pitching totals. ERA, WHIP and the per-nine rates are recomputed from the components rather than averaged; FIP needs each season’s own constant and is left to the season table.
Statistic	Zack Kelly	Angel Zerpa
G	115	160
GS	3	8
IP	131.1	189.2
W	8	12
L	8	9
SV	0	2
SO	127	158
BB	58	59
ERA	4.04	4.13
WHIP	1.31	1.37
K/9	8.7	7.5
BB/9	4.0	2.8
HR/9	1.1	1.1
WAR	0.6	1.3

Zack Kelly’s full profile →Angel Zerpa’s full profile →

More head to heads

The same seasons, measured against somebody else.

Zack Kelly vs

Angel Zerpa vs

How these are computed

FIP uses the constant solved from this season’s own runs, and FIP− is park-adjusted against the same league. dbWAR is our own open implementation — not fWAR or bWAR — and the full derivation, including its simplifications, is on the methodology page. To put these two beside a third, the comparison page takes up to four.