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Casey Janssen headshot

Pitcher · 2015

Casey Janssen

Age
34
B/T
R/R
Height
6' 4"
Weight
210 lb
Number
#44
Born
September 17, 1981 in Orange, CA, USA
MLB debut
April 27, 2006
dbWAR
.2
1 season(s)
IP
40.0
ERA
4.95
FIP
4.08
K/9
6.1
FIP−
103
100 = avg

Casey Janssen is a relief pitcher for the Washington Nationals. In 2015 he struck out 27 batters over 40.0 innings across 48 appearances, going 2-5. His ERA of 4.95 was 24.9% higher than the league average of 3.96 — the worst on his team, and 407th of 513 among MLB pitchers with 20+ innings. Stripping out defence, his 4.08 FIP suggests he pitched better than his ERA shows. He missed bats on 16.5% of swings (7.8% of every pitch he threw), walked 4.8% of the batters he faced and struck out 16.3%. His 0.2 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, 2015.

FIP4.08
K/96.1
WHIP1.15
WAR.2

Pitching

Standard and advanced, by season.

Trend
201548040.025038222784.954.081.156.11.81251030.2

Platoon splits

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

Opponent batting by the side the hitter bats from, 2015. Counted from play-by-play, so totals can differ from the box-score season line by a plate appearance or two.
SplitPAABHHRBBSOAVGOBPSLGwOBAK%
vs LHB605191610.176.263.294.23916.7%
vs RHB107102294317.284.308.500.34315.9%

Pitch sequencing

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

ShowBatter
Four-seamCutterCurveballSliderChangeupSinkerIN

Select a count to see exactly what Casey Janssen throws in it.

Pitch arsenal

What he throws, how hard, and how often it misses in 2015.

Four-Seam Fastball46.5%28288.31,71945.7%16.2%
Cutter24.4%14887.61,33441.9%13.9%
Curveball14.9%9073.71,66547.8%21.8%
Slider7.3%4483.875543.2%13.3%
Changeup2.6%1681.31,27325.0%33.3%
Sinker2.3%1488.91,63242.9%0.0%
Intentional Ball2.0%1279.81,5550.0%
Casey Janssen'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 Casey Janssen beside up to three others.

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Casey Janssen

Similar players

Nearest 2015 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.