Players · S · Pitcher · 2026

Reiver Sanmartin

San Francisco Giants National League West

Age: 30
B/T: L/L
Height: 6' 1"
Weight: 188 lb
Number: #48

Born: April 15, 1996 in Cartagena, Colombia
MLB debut: September 27, 2021

dbWAR: .3
IP: 21.1
ERA: 4.22
FIP: 4.41
K/9: 6.8
FIP−: 106

Reiver Sanmartin is a relief pitcher for the San Francisco Giants. In 2026 he struck out 16 batters over 21.1 innings across 24 appearances, going 3-0. His ERA of 4.22 is 1.0% higher than the league average of 4.18 — 14th of 25 on his team, and 300th of 538 among MLB pitchers with 20+ innings. Stripping out defence, his 4.41 FIP suggests the ERA was no fluke. He missed bats on 22.4% of swings (9.9% of every pitch he threw), walked 7.5% of the batters he faced and struck out 17.2%. His 0.1 dbWAR is built from that FIP rather than runs allowed, so it credits him for what he controls and not for the defence behind him.

League context

Percentile among qualified pitchers, 2026.

FIP4.41

K/96.8

WHIP1.36

WAR.1

WAR by season

Pitching

Standard and advanced, by season.


2026	SF	24	0	21.1	3	0	22	10	16	7	4.22	4.41	1.36	6.8	3.0	101	106	0.1
2025	CIN	1	0	1.2	0	0	2	0	2	1	0.00	2.54	1.80	10.8	5.4	0	61	0.0
2023	CIN	14	0	14.0	1	0	17	11	13	10	7.07	5.40	1.93	8.4	6.4	163	125	-0.1
2022	CIN	45	4	57.0	4	4	66	40	47	29	6.32	4.81	1.67	7.4	4.6	159	121	-0.1
2021	CIN	2	2	11.2	2	0	12	2	11	2	1.54	1.80	1.20	8.5	1.5	36	42	0.5

Batting

Standard and advanced, by season.

																					Trend
2022	CIN	1	2	0	0	0	0	0	1	.000	.000	.000	.000	.000	0.0%	50.0%	.000	-0.5	-114	-0.0
2021	CIN	2	6	0	0	0	0	0	5	.000	.000	.000	.000	.000	0.0%	83.3%	.000	-1.6	-112	-0.1

Platoon splits

How left- and right-handed hitters fare against him.

Season

Opponent batting by the side the hitter bats from, 2026. Counted from play-by-play, so totals can differ from the box-score season line by a plate appearance or two.
Split	PA	AB	H	HR	BB	SO	AVG	OBP	SLG	wOBA	K%
vs LHB	42	39	10	0	3	12	.256	.310	.333	.291	28.6%
vs RHB	51	46	12	3	4	4	.261	.320	.522	.355	7.8%

Pitch sequencing

What Reiver Sanmartin throws in each count, and what he follows each pitch with. Select any cell for the breakdown.

ShowBatter

SinkerChangeupSliderFour-seam

Select a count to see exactly what Reiver Sanmartin throws in it.

Pitch arsenal

What he throws, how hard, how often it misses, and what hitters do with it.

Season


Sinker	37.1%	128	91.7	2,299	52.3%	17.2%	30	.300	.810
Changeup	27.8%	96	86.5	2,179	38.5%	21.2%	29	.207	.534
Slider	27.0%	93	82.5	2,582	35.5%	34.3%	20	.200	.723
Four-Seam Fastball	8.1%	28	92.2	2,300	32.1%	14.3%	6	—	—

Reiver Sanmartin's arsenal by usage. Velocity is average release speed in mph, spin in rpm, and whiff rate is misses per swing — the cleanest single measure of whether a pitch beats hitters. BAA and OPS are what hitters did against each pitch, credited to the one that ended the plate appearance, and are left blank under 15 at-bats.

Head to head

Put Reiver Sanmartin beside up to three others.

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Reiver Sanmartin

Similar players

Nearest 2026 seasons by command, run prevention and role, on rate statistics rather than totals.

Blas CastañoCOL

ERA: 3.62
FIP: 4.68
SO: 21
WAR: 0.0

Very close

Albert SuárezBAL

ERA: 3.86
FIP: 4.25
SO: 46
WAR: 0.3

Very close

Pierce JohnsonCIN

ERA: 4.62
FIP: 4.68
SO: 42
WAR: -0.0

Very close

José A. FerrerSEA

ERA: 3.92
FIP: 4.00
SO: 54
WAR: 0.5

Very close

How these are computed

wOBA uses linear weights measured from this season's own play-by-play rather than published constants, and wRC+ is park-adjusted against that same league. dbWAR is our own open implementation — not fWAR or bWAR — and the full derivation, including its simplifications, is on the methodology page.