2026 Stats
W-L
3-3
ERA
3.73
WHIP
1.21
K
32
SV
18
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.
Records 18th save
O'Brien earned the save Tuesday against the Padres after tossing a scoreless ninth inning while allowing a walk.
Analysis
O'Brien has converted his last five save opportunities and has gone 18-for-22 so far in 2026. One of the most reliable ninth-inning relievers in the National League this season, O'Brien owns a 3.73 ERA and 1.21 WHIP across 31 appearances (31.1 innings) in 2026.
O'Brien has converted his last five save opportunities and has gone 18-for-22 so far in 2026. One of the most reliable ninth-inning relievers in the National League this season, O'Brien owns a 3.73 ERA and 1.21 WHIP across 31 appearances (31.1 innings) in 2026.
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
17
Last 10 Games
19
Last 5 Games
19
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
-5%
BAA vs LHP
2026
-16%
BAA vs RHP
| BAA | K | BB | H | HR | ||||
|---|---|---|---|---|---|---|---|---|
| Since 2024vs Left | .222 | 44 | 19 | 32 | 1 | |||
| Since 2024vs Right | .234 | 44 | 22 | 41 | 4 | |||
| 2026vs Left | .254 | 13 | 6 | 15 | 0 | |||
| 2026vs Right | .214 | 19 | 5 | 12 | 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
-50%
ERA at Home
2026
-59%
ERA on Road
| ERA | WHIP | IP | K/9 | BB/9 | |||||
|---|---|---|---|---|---|---|---|---|---|
| Since 2024Home | 2.42 | 1.16 | 48.1 | 7.1 | 3.0 | ||||
| Since 2024Away | 4.85 | 1.49 | 39.0 | 11.5 | 5.8 | ||||
| 2026Home | 5.00 | 1.56 | 18.0 | 7.5 | 3.0 | ||||
| 2026Away | 2.03 | 0.75 | 13.1 | 11.5 | 3.4 | ||||
| 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
2.91K/9
9.2BB/9
3.2HR/9
0.3Fastball
98.3 mphERA
3.73WHIP
1.21BABIP
.316GB/FB
2.81Left On Base
62.8%Exit Velocity
81.8 mphBarrels/BBE
5.1%Spin Rate
2269 rpmBalls Hit 95+ MPH
26.8%Swinging Strike
12.1%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
Holds on for 17th save
O'Brien secured the save Sunday against the Reds, allowing no runs on one hit and no walks in the ninth inning. He struck out one.
Analysis
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Nabs 15th save of season
O'Brien recorded his 15th save of the season in Wednesday's win over the Rangers. He tossed a scoreless ninth inning with one walk.
Analysis
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Earns 14th save
O'Brien earned the save in Friday's 6-5 win over the Cubs, allowing one run on one hit in the ninth inning. He did not record a walk or strikeout.
Analysis
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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
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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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Latest Fantasy Rumors
Carrying all-time high trade value
O'Brien could be a prime trade target ahead of this year's deadline, according to Mark Feinsand of MLB.com.
Analysis
O'Brien's trade value has never been higher, as the 31-year-old has emerged as the Cardinals' closer and still has four years of club control after 2026. Even though the Cards aren't out of the playoff race, the front office might elect to capitalize on his value while considering the long-term picture. O'Brien owns a 3.68 ERA and 1.16 WHIP across 29 appearances this season while going 17-for-21 in save chances.
O'Brien's trade value has never been higher, as the 31-year-old has emerged as the Cardinals' closer and still has four years of club control after 2026. Even though the Cards aren't out of the playoff race, the front office might elect to capitalize on his value while considering the long-term picture. O'Brien owns a 3.68 ERA and 1.16 WHIP across 29 appearances this season while going 17-for-21 in save chances.