2026 Stats
W-L
3-2
ERA
2.96
WHIP
0.99
K
27
SV
13
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.
Blows save Tuesday
O'Brien blew a save against the Pirates on Tuesday, allowing two runs on two hits and one walk over one inning.
Analysis
O'Brien was called upon to protect a two-run lead in the ninth inning. He couldn't get the job done, largely due to his own wildness -- in addition to giving up two singles, he also walked one and hit two Pirates batters. This was O'Brien's fourth blown save of the season, though he still is tied for the third in the league with 13 successful saves. He's held the opponent without an earned run in 19 of his 23 outings but has given up multiple runs in his other four appearances.
O'Brien was called upon to protect a two-run lead in the ninth inning. He couldn't get the job done, largely due to his own wildness -- in addition to giving up two singles, he also walked one and hit two Pirates batters. This was O'Brien's fourth blown save of the season, though he still is tied for the third in the league with 13 successful saves. He's held the opponent without an earned run in 19 of his 23 outings but has given up multiple runs in his other four appearances.
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
16
Last 10 Games
16
Last 5 Games
16
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
-11%
BAA vs LHP
2026
-6%
BAA vs RHP
| BAA | K | BB | H | HR | ||||
|---|---|---|---|---|---|---|---|---|
| Since 2024vs Left | .212 | 42 | 15 | 28 | 1 | |||
| Since 2024vs Right | .238 | 41 | 19 | 38 | 4 | |||
| 2026vs Left | .234 | 11 | 2 | 11 | 0 | |||
| 2026vs Right | .220 | 16 | 2 | 9 | 1 | |||
| 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
-60%
ERA at Home
2026
-68%
ERA on Road
| ERA | WHIP | IP | K/9 | BB/9 | |||||
|---|---|---|---|---|---|---|---|---|---|
| Since 2024Home | 1.91 | 1.06 | 42.1 | 7.2 | 2.6 | ||||
| Since 2024Away | 4.74 | 1.45 | 38.0 | 11.6 | 5.2 | ||||
| 2026Home | 4.50 | 1.42 | 12.0 | 8.3 | 1.5 | ||||
| 2026Away | 1.46 | 0.57 | 12.1 | 11.7 | 1.5 | ||||
| 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
6.75K/9
10.0BB/9
1.5HR/9
0.4Fastball
98.4 mphERA
2.96WHIP
0.99BABIP
.313GB/FB
3.60Left On Base
61.9%Exit Velocity
81.1 mphBarrels/BBE
4.3%Spin Rate
2283 rpmBalls Hit 95+ MPH
26.5%Swinging Strike
13.2%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 13th save
O'Brien earned the save Thursday against the Athletics, striking out two over a scoreless and hitless ninth inning.
Analysis
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Bounces back with save
O'Brien walked one and struck out none in a scoreless and hitless inning to earn the save in Tuesday's 6-4 win over the Athletics.
Analysis
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Blows third save
O'Brien blew the save in Sunday's 3-2 loss to San Diego. He allowed two runs on two hits and no walks while striking out three over one inning.
Analysis
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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
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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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Latest Fantasy Rumors
Seen as trade candidate
O'Brien could be a name to watch as the trade deadline approaches in July and the first days of August, according to Bob Nightengale of USA Today Sports.
Analysis
The Cardinals have been playing better than anyone would've expected in the first seven weeks of the season and currently sit eight games above .500 ahead of a three-game series against the Pirates, which begins Tuesday. However, if they experience some regression, they could still be open to trading players before the Aug. 3 deadline in order to continue their rebuilding process. O'Brien has gone 13-for-16 in save chances in 2026, posting a 2.45 ERA across 22 innings.
The Cardinals have been playing better than anyone would've expected in the first seven weeks of the season and currently sit eight games above .500 ahead of a three-game series against the Pirates, which begins Tuesday. However, if they experience some regression, they could still be open to trading players before the Aug. 3 deadline in order to continue their rebuilding process. O'Brien has gone 13-for-16 in save chances in 2026, posting a 2.45 ERA across 22 innings.