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Jairo Díaz headshot

Pitcher · 2020

Jairo Díaz

Age
29
B/T
R/R
Height
6' 0"
Weight
254 lb
Number
#47
Born
May 27, 1991 in Puerto La Cruz, Venezuela
MLB debut
September 8, 2014
dbWAR
.5
4 season(s)
IP
20.0
ERA
7.65
FIP
6.64
K/9
7.7
FIP−
149
100 = avg

Jairo Díaz is a relief pitcher for the Colorado Rockies. In 2020 he struck out 17 batters over 20.0 innings across 24 appearances, going 1-2. His ERA of 7.65 was 71.8% higher than the league average of 4.45 — the second worst on his team, and 310th of 323 among MLB pitchers with 20+ innings. Stripping out defence, his 6.64 FIP suggests he pitched better than his ERA shows. He missed bats on 23.5% of swings (10.7% of every pitch he threw), walked 13.2% of the batters he faced and struck out 16.0%. His -0.4 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, 2020.

FIP6.64
K/97.7
WHIP2.25
WAR-.4

Pitching

Standard and advanced, by season.

Trend
202024020.0124311717147.656.642.257.76.3172149-0.4
201956057.2645562963194.533.701.309.83.0100820.7
2017405.0000125259.005.963.403.69.0207137-0.1
201521019.00101651862.373.551.168.52.860900.2

Platoon splits

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

Opponent batting by the side the hitter bats from, 2020. Counted from play-by-play, so totals can differ from the box-score season line by a plate appearance or two.
SplitPAABHHRBBSOAVGOBPSLGwOBAK%
vs LHB504113469.317.396.683.44118.0%
vs RHB564418088.409.518.545.46114.3%

Pitch sequencing

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

ShowBatter
SliderSinkerFour-seam

Select a count to see exactly what Jairo Díaz throws in it.

Pitch arsenal

What he throws, how hard, and how often it misses in 2020.

Slider42.0%15385.22,35044.4%31.4%
Sinker36.0%13195.02,11236.6%18.0%
Four-Seam Fastball22.0%8095.22,16935.0%17.1%
Jairo Díaz'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.

Head to head

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Jairo Díaz

Similar players

Nearest 2020 seasons by command, run prevention and role, on rate statistics rather than totals.

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.