Relief Pitcher · St. Louis Cardinals
Riley O'Brien
ERA
2.94
FIP
–
IP
52.0
W-L
3-4
WHIP
1.12
K%
24.3
BB%
10.1
GB%
–
K/9
9.2
HR/9
0.3
Drafted by the Tampa Bay Rays in 2017 (round 8), he was acquired by the St. Louis Cardinals via trade from the Seattle Mariners in November 2023. He made his MLB debut on September 28, 2021.Facts: MLB StatsAPI (people · transactions)
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Sinker
SI · lead pitch54% of pitches · .339 xwOBA allowed · 264 BIP · where it goes, what it costs
Pitcher Locations
where he throws it · catcher’s view
Rare 0% · Common 10% · Very common 20%+
xwOBA Allowed
damage done by zone · all batters
Cold .200 · Avg .310 · Hot .500+
Expected Damage
locations × damage zones
Low risk · Average · High-risk zone
Sinker (54% usage) has allowed .339 xwOBA over 264 balls in play — his most-used pitch.
Arsenal
usage × whiff, ranked5 pitch types · 1,890-pitch sample · 2026/2025/2024 blend, weighted 4/3/1
Whiff% Trend
last 8 outings · by pitch · min 5 swings per point
SinkerSweeperSlider
Hand Splits
K% + xwOBA allowed by batter side · 2026/2025/2024 blend, weighted 4/3/1
| Split | K% | xwOBA | Sample |
|---|---|---|---|
| vs. LHB | 24.9 | .325 | 208 |
| vs. RHB | 23.6 | .308 | 245 |
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Market lines
current pick’em lines by book · updates through the day
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DFS picks
today’s picks for this pitcher, probability-sorted · graded nightly
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