2026 Stats
W-L
3-1
ERA
2.00
WHIP
0.89
K
20
SV
11
Rest-of-Season Projections
2026 Fantasy Outlook
O'Brien opened 2025 in the minors, striking out 32 in 19.1 innings at Triple-A Memphis before he was recalled for his first extended look in the majors. The 30-year-old completed a career-high 48.0 innings for St. Louis, tossing his 98 mph sinker nearly half of the time to suppress hard contact and produce a 54 percent ground ball rate. He didn't strike many batters out and walked more than you'd like to see - his 11.6 K-BB percentage ranked 137th out of the 191 relievers who threw 40-plus innings last year - but the Cardinals' flurry of relief pitcher trades opened up high-leverage opportunities for O'Brien. The right-hander closed out 2025 by racking up four of the last five saves for St. Louis. That puts him in the mix for early 2026 save opportunities, particularly if he throws more curveballs (21 percent pitch usage). O'Brien's curve held opposing hitters to a .059 BA (3rd for that pitch type among those who threw 100+ curveballs) and produced a 50.9 percent whiff rate (4th). Read Past Outlooks
Signed a one-year contract with the Cardinals in March of 2026.
Converts 11th save
O'Brien struck out one in a perfect inning to earn the save in Thursday's 2-1 win over the Padres.
Analysis
O'Brien got the job done on 10 pitches (eight strikes) to preserve a one-run lead. He's had some shaky moments lately, allowing four runs over his last 4.2 innings, but he's still converted four of his five save chances in that span. This is O'Brien's first full season closing, and he's done well in the role with 11 saves on 13 chances while maintaining a 2.00 ERA, 0.89 WHIP and 20:1 K:BB through 18 innings.
O'Brien got the job done on 10 pitches (eight strikes) to preserve a one-run lead. He's had some shaky moments lately, allowing four runs over his last 4.2 innings, but he's still converted four of his five save chances in that span. This is O'Brien's first full season closing, and he's done well in the role with 11 saves on 13 chances while maintaining a 2.00 ERA, 0.89 WHIP and 20:1 K:BB through 18 innings.
Pitching Stats
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2026 MLB Game Log
2026
2025
2024
2022
2021
Minor League Game Log
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Pitching Appearances Breakdown
Average Pitch Count
15
Last 10 Games
16
Last 5 Games
18
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 2024
-13%
BAA vs LHP
2026
-1%
BAA vs RHP
| BAA | K | BB | H | HR | ||||
|---|---|---|---|---|---|---|---|---|
| Since 2024vs Left | .208 | 42 | 13 | 26 | 1 | |||
| Since 2024vs Right | .240 | 34 | 18 | 35 | 3 | |||
| 2026vs Left | .225 | 11 | 0 | 9 | 0 | |||
| 2026vs Right | .222 | 9 | 1 | 6 | 0 | |||
| 2025vs Left | .157 | 27 | 9 | 11 | 0 | |||
| 2025vs Right | .224 | 18 | 13 | 22 | 2 | |||
| 2024vs Left | .400 | 4 | 4 | 6 | 1 | |||
| 2024vs Right | .333 | 7 | 4 | 7 | 1 | |||
| More Splits→ | View More Split Stats | |||||||
Home/Away Pitching Splits
Since 2024
-68%
ERA at Home
2026
-100%
ERA on Road
| ERA | WHIP | IP | K/9 | BB/9 | |||||
|---|---|---|---|---|---|---|---|---|---|
| Since 2024Home | 1.56 | 1.02 | 40.1 | 7.6 | 2.5 | ||||
| Since 2024Away | 4.81 | 1.51 | 33.2 | 11.2 | 5.3 | ||||
| 2026Home | 3.60 | 1.30 | 10.0 | 9.9 | 0.9 | ||||
| 2026Away | 0.00 | 0.38 | 8.0 | 10.1 | 0.0 | ||||
| 2025Home | 0.66 | 0.88 | 27.1 | 6.9 | 2.6 | ||||
| 2025Away | 3.92 | 1.50 | 20.2 | 10.5 | 6.1 | ||||
| 2024Home | 3.00 | 1.33 | 3.0 | 6.0 | 6.0 | ||||
| 2024Away | 16.20 | 3.40 | 5.0 | 16.2 | 10.8 | ||||
| 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
20.00K/9
10.0BB/9
0.5HR/9
0.0Fastball
98.4 mphERA
2.00WHIP
0.89BABIP
.328GB/FB
4.14Left On Base
68.8%Exit Velocity
81.8 mphBarrels/BBE
4.8%Spin Rate
2302 rpmBalls Hit 95+ MPH
27.7%Swinging Strike
12.4%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
Tallies 10th save
O'Brien picked up the save in Monday's 6-3 victory over Milwaukee. He allowed no hits or walks with no strikeouts over two-thirds of a perfect inning.
Analysis
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Barely holds on for ninth save
O'Brien notched the save Saturday against the Dodgers, allowing two runs on four hits and no walks in the ninth inning. He struck out two.
Analysis
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Hangs on for eighth save
O'Brien secured the save Wednesday against the Pirates, allowing no runs on one hit and no walks in the ninth inning. He struck out one.
Analysis
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Blows second save
O'Brien (3-1) blew the save and took the loss Saturday as the Cardinals fell 11-9 to the Mariners, giving up two runs on four hits and a walk in an inning of work. He struck out one and also hit a batter with a pitch.
Analysis
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Notches seventh save
O'Brien gave up a hit and struck out one in a scoreless ninth inning Tuesday to record his seventh save of the season in a 5-3 win over the Marlins.
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.