2025 Stats
W-L
1-0
ERA
1.56
WHIP
1.18
K
34
SV
2
Rest-of-Season Projections
Signed a one-year contract with the Cardinals in March of 2025.
Shuts door on Marlins
O'Brien earned the save in a 7-4 win over the Marlins on Tuesday. He did not allow a hit but walked two and also struck out two in a scoreless inning.
Analysis
O'Brien was called upon for the save chance after JoJo Romero pitched against the heart of the Miami order in the eighth. Things did not begin well for O'Brien, who walked consecutive batters to open up the inning, but he rebounded with back-to-back strikeouts before getting a groundout to end the game. O'Brien now has two saves to Romero's three since the departure of Ryan Helsley at the deadline. O'Brien has found his footing this season, posting a 1.56 ERA, 1.18 WHIP and 34:17 K:BB in 34.2 innings.
O'Brien was called upon for the save chance after JoJo Romero pitched against the heart of the Miami order in the eighth. Things did not begin well for O'Brien, who walked consecutive batters to open up the inning, but he rebounded with back-to-back strikeouts before getting a groundout to end the game. O'Brien now has two saves to Romero's three since the departure of Ryan Helsley at the deadline. O'Brien has found his footing this season, posting a 1.56 ERA, 1.18 WHIP and 34:17 K:BB in 34.2 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
14
Last 5 Games
15
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
-19%
BAA vs LHP
2025
-37%
BAA vs LHP
| BAA | K | BB | H | HR | ||||
|---|---|---|---|---|---|---|---|---|
| Since 2023vs Left | .206 | 24 | 11 | 13 | 1 | |||
| Since 2023vs Right | .253 | 21 | 14 | 24 | 3 | |||
| 2025vs Left | .146 | 20 | 7 | 7 | 0 | |||
| 2025vs Right | .230 | 14 | 10 | 17 | 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
-87%
ERA at Home
2025
-84%
ERA at Home
| ERA | WHIP | IP | K/9 | BB/9 | |||||
|---|---|---|---|---|---|---|---|---|---|
| Since 2023Home | 0.81 | 1.12 | 22.1 | 7.7 | 3.6 | ||||
| Since 2023Away | 6.20 | 1.82 | 20.1 | 11.5 | 7.1 | ||||
| 2025Home | 0.47 | 1.09 | 19.1 | 7.9 | 3.3 | ||||
| 2025Away | 2.93 | 1.30 | 15.1 | 10.0 | 5.9 | ||||
| 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
8.8BB/9
4.4HR/9
0.5Fastball
98.3 mphERA
1.56WHIP
1.18BABIP
.257GB/FB
2.25Left On Base
89.0%Exit Velocity
83.0 mphBarrels/BBE
3.0%Spin Rate
2298 rpmBalls Hit 95+ MPH
22.4%Swinging Strike
10.8%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
Locks down first save
O'Brien earned the save in Wednesday's 5-3 win over the Dodgers, issuing one walk with no hits or strikeouts over 1.1 scoreless innings.
Analysis
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Excelling out of St. Louis bullpen
O'Brien has permitted just one run and boasts a 20:8 K:BB over 16 innings covering his last 12 appearances.
Analysis
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Back with big club
The Cardinals recalled O'Brien from Triple-A Memphis on Monday.
Analysis
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Back to minors after doubleheader
The Cardinals optioned O'Brien to Triple-A Memphis on Friday.
Analysis
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Up as 27th man for doubleheader
The Cardinals recalled O'Brien from Triple-A Memphis on Thursday.
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.