2025 Stats
W-L
3-0
ERA
2.13
WHIP
1.18
K
40
SV
4
Rest-of-Season Projections

Secures fourth save
O'Brien picked up the save in Sunday's 3-1 win at Milwaukee, allowing one walk and no hits over a scoreless inning with two strikeouts.
Analysis
The 30-year-old worked around a two-out walk to collect his second save of the month. O'Brien, who fired 10 of his 16 total pitches for strikes, got the ninth after JoJo Romero pitched a scoreless frame in the eighth against the heart of the Brewers lineup. Although Romero is likely to draw the majority of save opportunities, St. Louis manager Oliver Marmol has shown no hesitation in employing O'Brien when the situation arises. The righty reliever now sports a 2.13 ERA, 1.17 WHIP and 40:20 K:BB in 42.1 total innings.
The 30-year-old worked around a two-out walk to collect his second save of the month. O'Brien, who fired 10 of his 16 total pitches for strikes, got the ninth after JoJo Romero pitched a scoreless frame in the eighth against the heart of the Brewers lineup. Although Romero is likely to draw the majority of save opportunities, St. Louis manager Oliver Marmol has shown no hesitation in employing O'Brien when the situation arises. The righty reliever now sports a 2.13 ERA, 1.17 WHIP and 40:20 K:BB in 42.1 total innings.
Pitching Stats
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2025 MLB Game Log
2025
2024
2022
2021
Minor League Game Log
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Pitching Appearances Breakdown
Average Pitch Count
19
Last 10 Games
17
Last 5 Games
17
How many pitches does Riley O'Brien generally throw?
1-10
11-20
21-30
31-40
41-50
51-60
61-70
71-80
81-90
91-100
101-110
111-120
121+
What part of the game does Riley O'Brien generally pitch?
1st
2nd
3rd
4th
5th
6th
7th
8th
9th
Extra
% Games Reaching Innings Threshold
% Games By Number of Innings Pitched
Left/Right Pitching Splits
Since 2023
-17%
BAA vs LHP
2025
-31%
BAA vs LHP
BAA | K | BB | H | HR | ||||
---|---|---|---|---|---|---|---|---|
Since 2023vs Left | .208 | 28 | 12 | 16 | 1 | |||
Since 2023vs Right | .252 | 23 | 16 | 27 | 3 | |||
2025vs Left | .161 | 24 | 8 | 10 | 0 | |||
2025vs Right | .233 | 16 | 12 | 20 | 2 | |||
2024vs Left | .400 | 4 | 4 | 6 | 1 | |||
2024vs Right | .333 | 7 | 4 | 7 | 1 | |||
2023vs Left | 0 | 0 | 0 | 0 | 0 | |||
2023vs Right | 0 | 0 | 0 | 0 | 0 | |||
More Splits→ | View More Split Stats |
Home/Away Pitching Splits
Since 2023
-85%
ERA at Home
2025
-81%
ERA at Home
ERA | WHIP | IP | K/9 | BB/9 | |||||
---|---|---|---|---|---|---|---|---|---|
Since 2023Home | 1.00 | 1.00 | 27.0 | 7.0 | 3.0 | ||||
Since 2023Away | 6.56 | 1.89 | 23.1 | 11.6 | 7.3 | ||||
2025Home | 0.75 | 0.96 | 24.0 | 7.1 | 2.6 | ||||
2025Away | 3.93 | 1.47 | 18.1 | 10.3 | 6.4 | ||||
2024Home | 3.00 | 1.33 | 3.0 | 6.0 | 6.0 | ||||
2024Away | 16.20 | 3.40 | 5.0 | 16.2 | 10.8 | ||||
2023Home | 0 | 0 | 0 | 0 | 0 | ||||
2023Away | 0 | 0 | 0 | 0 | 0 | ||||
More Splits→ | View More Split Stats |
Stat Review
How does Riley O'Brien compare to other relievers?
This section compares his stats with all relief pitcher seasons from the previous three seasons (minimum 30 innings)*. The bar represents the player's percentile rank. For example, if the bar is halfway across, then the player falls into the 50th percentile for that stat and it would be considered average.
* Exit Velocity, Barrels/BBE %, Balls Hit 95+ MPH %, and Spin Rate are benchmarked against 2019 data (min 30 IP). See here for more exit velocity/barrels stats plus an explanation of current limitations with that data set.
* Exit Velocity, Barrels/BBE %, Balls Hit 95+ MPH %, and Spin Rate are benchmarked against 2019 data (min 30 IP). See here for more exit velocity/barrels stats plus an explanation of current limitations with that data set.
K/BB
2.00K/9
8.5BB/9
4.3HR/9
0.4Fastball
98.1 mphERA
2.13WHIP
1.18BABIP
.261GB/FB
2.43Left On Base
80.5%Exit Velocity
81.6 mphBarrels/BBE
2.5%Spin Rate
2300 rpmBalls Hit 95+ MPH
22.2%Swinging Strike
11.1%Advanced Pitching Stats
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Defensive Stats
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Stats Vs Today's Lineup
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More Fantasy News

Pulled from save opportunity
O'Brien was charged with three runs and pulled from a save chance without recording an out in Saturday's loss to the Brewers.
Analysis
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Collects seventh save
O'Brien earned the save in Sunday's 4-3 win over the Giants, allowing one hit in a scoreless ninth.
Analysis
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Picks up win in return appearance
O'Brien (3-0) struck out one in a scoreless frame and was credited with a win in Saturday's victory over the Giants.
Analysis
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Could be available this weekend
The Cardinals are hopeful O'Brien (shoulder) will be available to pitch Friday against the Giants, the St. Louis Post-Dispatch reports.
Analysis
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Plays catch, could avoid IL
O'Brien (shoulder) was cleared to play catch Monday and could avoid the 15-day injured list, Daniel Guerrero of the St. Louis Post-Dispatch reports.
Analysis
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Latest Fantasy Rumors

Eligible for promotion Monday
O'Brien will be eligible to be recalled by the Cardinals on Monday, and Jeff Jones of the Belleville News-Democrat speculates the right-hander could be called up from Triple-A Memphis at some point this week.
Analysis
O'Brien could have joined the Cardinals over the past couple weeks if the corresponding move was an IL transaction, but he's stayed a Triple-A for the full 15 days. The 29-year-old has made just one appearance in the majors this season but has been dominant in 13 outings for Memphis with a 1.46 ERA, 0.99 WHIP and 9:5 K:BB over 12.1 innings.
O'Brien could have joined the Cardinals over the past couple weeks if the corresponding move was an IL transaction, but he's stayed a Triple-A for the full 15 days. The 29-year-old has made just one appearance in the majors this season but has been dominant in 13 outings for Memphis with a 1.46 ERA, 0.99 WHIP and 9:5 K:BB over 12.1 innings.