Riley O'Brien earns All-Star nod in first full MLB season
St. Louis Cardinals closer Riley O'Brien has been named to the 2026 National League All-Star team during his first full major league season. The 31-year-old right-hander earned his first career All-Star nod as a pitching replacement, validating a rapid rise from journeyman reliever to one of the NL's top closers. He slots into a playoff-chasing St. Louis roster that sent three first-time All-Stars to Philadelphia this week.
O'Brien joins fellow Cardinals Jordan Walker and Iván Herrera as first-time All-Stars heading into All-Star Week. Walker already made headlines by winning the Home Run Derby on Monday night, and now the bullpen anchor completes a rare trio of breakthrough stars from one franchise.
Key Takeaways
- Riley O'Brien was added to the 2026 NL All-Star roster on Tuesday as a pitching replacement, earning his first career selection.
- The Cardinals closer has 22 saves in 26 opportunities and sits one off the NL lead, with only one blown save since May 10.
- O'Brien opened 2026 with 13 scoreless appearances and posted seven straight scoreless outings ahead of All-Star Week.
- Acquired from Seattle for cash in 2023, the Seattle native is now drawing renewed trade interest from the Mariners.
- O'Brien remains under Cardinals control through 2030, complicating any deadline deal for St. Louis.
Why Did Riley O'Brien Make the All-Star Team?
MLB added O'Brien to the National League roster Tuesday after another pitcher exited the roster, giving the Cardinals a third first-time All-Star this season. His numbers justify the honor: 22 saves from 26 chances, a 3.72 ERA, and a 1.156 WHIP through his first full campaign as St. Louis' primary closer.
Per Sodo Mojo, O'Brien ranks one save behind the NL leader and has been nearly automatic since mid-May. His sinker has averaged a career-best 98.3 mph, and he has dominated right-handed hitters with a .190 batting average against.
How Did O'Brien Rise From Journeyman to Cardinals Closer?
The path was anything but linear. St. Louis acquired O'Brien from the Seattle Mariners in 2023 for cash considerations when he had just two big league appearances. He struggled in 2024, was sent back to Triple-A, then rebounded with a 2.06 ERA across 42 outings last season after the club reshaped its bullpen at the trade deadline.
This year, the Cardinals handed him the ninth inning full time. O'Brien did not allow an earned run over his first 13 appearances and has given up earned runs in only eight of 39 outings, according to Yahoo Sports. He told reporters Monday that early dominance, a midseason rough patch, and renewed comfort in the role all shaped his breakout.
"Start of the season, it felt like I was lights out," O'Brien said, per MLB.com's Brenden Schaeffer. "The more I kept throwing in the ninth inning, late innings in games, I just felt more comfortable. Just settling into the role, knowing that the ninth inning is mine -- just all the prep and the mental preparation, too -- I think it's just being comfortable in that role now."
Could the Mariners Bring Riley O'Brien Home in a Trade?
Seattle's bullpen needs reinforcements before the Aug. 3 trade deadline, and O'Brien's All-Star résumé only raises his profile as a target. Sodo Mojo identified him as an ideal fit last week, noting his ground-ball profile, sweeper whiff rate, and ability to stabilize a pen missing injured arms until August.
Any deal is far from simple. O'Brien is under club control through 2030, and the Cardinals remain in the Wild Card mix despite a recent slump. Still, the two front offices know each other well after the Brendan Donovan negotiations, and bringing a Seattle native home would rewrite a 2023 trade many Mariners fans now regret.
What Does the All-Star Nod Mean for St. Louis?
For the Cardinals, O'Brien's selection confirms that a retooling roster has found legitimate cornerstone talent. He is part of the reason St. Louis has stayed in the playoff hunt, and his presence gives manager Oliver Marmol a reliable late-inning option on a team still defining its long-term core.
More coverage of breakout stars and late-breaking sports headlines is available in our Celebrity Breaking News section. For official roster details, see MLB.com's All-Star report.