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2026
Justin Haley headshot

Pitcher · 2018

Justin Haley

Age
27
B/T
L/R
Height
6' 5"
Weight
230 lb
Born
June 16, 1991 in Sacramento, CA, USA
MLB debut
April 5, 2017
dbWAR
-.3
2 season(s)
IP
7.2
ERA
4.70
FIP
7.73
K/9
0.0
FIP−
186
100 = avg

Justin Haley is a relief pitcher for the Boston Red Sox. In 2018 he struck out 0 batters over 7.2 innings across 4 appearances, going 0-0. His ERA of 4.70 was 13.2% higher than the league average of 4.15. Stripping out defence, his 7.73 FIP suggests that his ERA had some help behind him. He missed bats on 9.7% of swings (4.7% of every pitch he threw), walked 8.6% of the batters he faced and struck out 0.0%. His -0.3 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, 2018.

FIP7.73
K/90.0
WHIP1.70
WAR-.3

Pitching

Standard and advanced, by season.

Trend
2018407.2000104034.707.731.700.03.5113186-0.3
201710018.000122121466.004.941.567.03.0138113-0.0

Platoon splits

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

Opponent batting by the side the hitter bats from, 2018. Counted from play-by-play, so totals can differ from the box-score season line by a plate appearance or two.
SplitPAABHHRBBSOAVGOBPSLGwOBAK%
vs LHB12104110.400.417.800.4820.0%
vs RHB23216120.286.348.476.3580.0%

Pitch sequencing

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

ShowBatter
Four-seamSliderCurveballSinkerChangeup

Select a count to see exactly what Justin Haley throws in it.

Pitch arsenal

What he throws, how hard, and how often it misses in 2018.

Four-Seam Fastball56.6%7391.92,04838.4%5.6%
Slider23.3%3087.42,40650.0%22.2%
Curveball14.0%1878.12,34233.3%0.0%
Justin Haley'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

Put Justin Haley beside up to three others.

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Justin Haley
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.