Riley O'Brien

RP · R/R · age 31.6 · STL

OUT OF OPTIONSXX-DSUPER TWO?OCTOBER OK

Roster status
ACTIVE
Service thru 2025
1+129
Service now / projected
2+129 / 2+129
Option years left (2026)
0
Assignments left this season
n/a of 5
Contract (2027)
SALARY ARBITRATION ELIGIBLE ("SUPER TWO") OR PRE-ARBITRATION / AUTO-RENEWAL (TBD)
Acquired
Purchased (SEA) Nov'23
Outrighted / DFA'd before
1 / 2
Contract
1 yr, $795.05k (2026)

Next 90 days, by the model

Stays put
81%
Designated
4%
Optioned
<1%
Traded
15%
Released or non-tendered
<1%

Pushing the cut risk around: age (31.60) raises it, this season's innings (60) lowers it, prior DFAs (2) raises it.

Context the model does not weigh: ZiPS projects 0.1 WAR, 0.4 WAR this season; 14 RP on the 40-man.

Trained on every 40-man roster snapshot since 2011 and what happened in the following 90 days; it sees roster status, options, service, history and last season's line, not this season's performance or the club's intentions. How well it does.

Is there a job for him next year?

STL returns 14 RP on the 40-man once nobody leaves; about 9 RP jobs survive a normal winter. By his own recent record he ranks 3rd among the returners (0.6 WAR against a bar of 0.0), which the calibrated model turns into 70% kept through the tender deadline. Ranked by ZiPS and Steamer instead, which credit his longer track record, he is 3rd (0.2 WAR, bar 0.1), worth 71% kept on the same model.

By recent record: returning RPProj. WAR
1. Matt Svanson0.8
2. Gordon Graceffo0.7
3. Riley O'Brien0.6
4. Justin Bruihl0.3
5. Ryan Fernandez0.3
6. Cooper Hjerpe0.2
7. Cade Winquest0.2
8. Max Rajcic0.0
9. Luis Gastelumlast job0.0
10. Ryne Stanek-0.0
11. Peter Strzelecki-0.1
12. Brycen Mautz-0.5
By ZiPS / Steamer: returning RPProj. WAR
1. Gordon Graceffo0.5
2. Brycen Mautz0.4
3. Riley O'Brien0.2
4. Matt Svanson0.2
5. Ryne Stanek0.2
6. Luis Gastelum0.2
7. Hancel Rincon0.2
8. Ryan Fernandez0.2
9. Max Rajciclast job0.1
10. Justin Bruihl0.1
11. Cade Winquest0.0
12. Cooper Hjerpe0.0

Departing free agents are excluded; players on club, mutual or player options are counted as returning. The kept probability is calibrated on every September since 2012 using the recent-record projection; the ZiPS/Steamer reading uses the same model with a different ranking, so treat it as a second opinion rather than a calibrated number. Salary enters once arbitration projections publish in October.

October: Post-season eligible

On the 40-man before noon ET Sep 1. He stays eligible as long as he remains on the 40-man or 60-day IL through the post-season; an outright after the cutoff would end automatic eligibility.

The post-season eligibility list is fixed at noon ET on September 1: everyone on the 40-man, the 60-day IL or the military list at that moment, who then stays there without interruption. Attachment 25 (Major League Rule 40)

What happens if the club…

option him to the minorsBLOCKED
Out of options: the only route to the minors is outright waivers, where any club can claim him for $50,000.
Out of options
designate him for assignment (or put him on outright waivers)
The club has 7 days to trade him, pass him through outright waivers, or release him; he is paid at the major-league rate and keeps accruing service in the meantime. On outright waivers any club can claim him for $50,000, worst record first, and the claiming club takes his contract (1 yr, $795.05k (2026)). He was outrighted before (1x) give him the Article XX-D choice: elect free agency immediately (giving up the rest of his salary) or accept the assignment, keep getting paid, and elect free agency after the season unless he is added back to a 40-man first. Post-season: an outright after the September 1 cutoff ends his automatic eligibility. He could only return as an approved injury replacement, and only if he accepts the outright and stays on a minor-league reserve list in the organization without interruption; a release makes him ineligible for anyone this October.
Designated for assignment: 7 days · Outright waivers · Article XX-D: the right to walk
release him
Release waivers cost a claiming club $1 but the claimant assumes the whole contract, so expensive players clear. The club owes the full unpaid balance of this season's salary, offset by whatever another club pays him this year. A released player is not post-season eligible for any club this year.
Release waivers and termination pay · Which rate a split contract pays at release
trade himBLOCKED
Not now: players on major-league contracts cannot be traded after the Aug 3 deadline until the day after the World Series.
Trade deadline · 10-and-5 rights · June 15 no-trade for free-agent signees
non-tender him
At the tender deadline (Nov 20) the club can decline to offer a contract: no waivers, no termination pay, and he can be re-signed the same night. Tendering means arbitration, where he cannot be cut more than 20% from this year's salary.
Tender deadline · Arbitration: 3 to 6 years · Maximum salary cut

What the rules say about him

Option years, season by season

SeasonDays on optionOption year usedStints
202575yesMar 15, 2025 to Apr 25, 2025 (38d, spring training)May 2, 2025 to Jun 5, 2025 (34d)Jun 6, 2025 to Jun 9, 2025 (3d)
202416no (under 20)Aug 11, 2024 to Aug 27, 2024 (16d)
202243yesMar 27, 2022 to Apr 13, 2022 (6d, spring training)Apr 17, 2022 to May 5, 2022 (18d)May 8, 2022 to May 27, 2022 (19d)
2021184yesMar 12, 2021 to Sep 28, 2021 (180d, spring training)Sep 30, 2021 to Oct 5, 2021 (4d)

Transaction log

Jul 13, 2026Status changeNational League All-Stars activated RHP Riley O'Brien.
Jun 9, 2025RecalledSt. Louis Cardinals recalled RHP Riley O'Brien from Memphis Redbirds.
Jun 6, 2025OptionedSt. Louis Cardinals optioned RHP Riley O'Brien to Memphis Redbirds.
Jun 5, 2025RecalledSt. Louis Cardinals recalled RHP Riley O'Brien from Memphis Redbirds.
May 2, 2025OptionedSt. Louis Cardinals optioned RHP Riley O'Brien to Memphis Redbirds.
Apr 25, 2025RecalledSt. Louis Cardinals recalled RHP Riley O'Brien from Memphis Redbirds.
Mar 15, 2025OptionedSt. Louis Cardinals optioned RHP Riley O'Brien to Memphis Redbirds.
Aug 27, 2024RecalledSt. Louis Cardinals recalled RHP Riley O'Brien from Memphis Redbirds.
Aug 11, 2024OptionedSt. Louis Cardinals optioned RHP Riley O'Brien to Memphis Redbirds.
Aug 11, 2024Status changeSt. Louis Cardinals activated RHP Riley O'Brien from the 60-day injured list.
May 10, 2024Status changeSt. Louis Cardinals transferred RHP Riley O'Brien from the 15-day injured list to the 60-day injured list. Right forearm flexor strain.
Mar 31, 2024Status changeSt. Louis Cardinals placed RHP Riley O'Brien on the 15-day injured list retroactive to March 29, 2024. Right forearm flexor strain.
Nov 5, 2023TradedSeattle Mariners traded RHP Riley O'Brien to St. Louis Cardinals for cash.
Jun 2, 2022OutrightedSeattle Mariners sent RHP Riley O'Brien outright to Tacoma Rainiers.
May 27, 2022Designated for assignmentSeattle Mariners designated RHP Riley O'Brien for assignment.
May 8, 2022OptionedSeattle Mariners optioned RHP Riley O'Brien to Tacoma Rainiers.
May 5, 2022RecalledSeattle Mariners recalled RHP Riley O'Brien from Tacoma Rainiers.
Apr 17, 2022OptionedSeattle Mariners optioned RHP Riley O'Brien to Tacoma Rainiers.
Apr 13, 2022Designated for assignmentCincinnati Reds designated RHP Riley O'Brien for assignment.
Mar 27, 2022OptionedCincinnati Reds optioned RHP Riley O'Brien to Louisville Bats.
Oct 5, 2021RecalledCincinnati Reds recalled RHP Riley O'Brien from Louisville Bats.
Sep 30, 2021OptionedCincinnati Reds optioned RHP Riley O'Brien to Louisville Bats.
Sep 28, 2021RecalledCincinnati Reds recalled RHP Riley O'Brien from Louisville Bats.
Mar 12, 2021OptionedCincinnati Reds optioned P Riley O'Brien to Louisville Bats.
Nov 20, 2020Contract selectedCincinnati Reds selected the contract of RHP Riley O'Brien from Chattanooga Lookouts.
Aug 28, 2020TradedTampa Bay Rays traded Riley O'Brien to Cincinnati Reds for LHP Cody Reed.
Jun 20, 2017SignedTampa Bay Rays signed RHP Riley O'Brien.

Service through 2025 per FanGraphs RosterResource; options and this-season service reconstructed from the MLB transaction log (reconstruction; FanGraphs shows 0). Rule 5 exposure deadline Nov 17, 2026.