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Marc Rzepczynski headshot

Pitcher · 2018

Marc Rzepczynski

Age
33
B/T
L/L
Height
6' 2"
Weight
220 lb
Born
August 29, 1985 in Oak Lawn, IL, USA
MLB debut
July 7, 2009
dbWAR
.9
4 season(s)
IP
10.1
ERA
6.97
FIP
6.45
K/9
9.6
FIP−
155
100 = avg

Marc Rzepczynski is a relief pitcher for the Seattle Mariners. In 2018 he struck out 11 batters over 10.1 innings across 23 appearances, going 0-1. His ERA of 6.97 was 67.9% higher than the league average of 4.15. Stripping out defence, his 6.45 FIP suggests he pitched better than his ERA shows. He missed bats on 30.9% of swings (13.6% of every pitch he threw), walked 17.5% of the batters he faced and struck out 19.3%. 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, 2018.

FIP6.45
K/99.6
WHIP2.52
WAR-.2

Pitching

Standard and advanced, by season.

Trend
201823010.101016811106.976.452.529.68.7168155-0.2
201764031.1221291425204.024.401.567.25.7921010.1
201670047.2100461446292.643.571.578.75.563850.6
201572035.0240402241145.663.361.5410.53.6143850.4

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 LHB36318059.258.361.387.33825.0%
vs RHB21168252.500.619.938.6259.5%

Pitch sequencing

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

ShowBatter
SinkerSliderChangeup

Select a count to see exactly what Marc Rzepczynski throws in it.

Pitch arsenal

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

Sinker54.0%11591.92,05744.3%21.2%
Slider37.1%7984.12,37244.3%48.4%
Changeup8.9%1986.21,67826.3%27.3%
Marc Rzepczynski'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 Marc Rzepczynski beside up to three others.

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Marc Rzepczynski
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.