Aug 19, 2025; Miami, Florida, USA; St. Louis Cardinals catcher Pedro Pagés (43) celebrates a win with pitcher Riley O'Brien (55) against the Miami Marlins at loanDepot Park. Mandatory Credit: Jim Rassol-Imagn Images Jim Rassol-Imagn Images

Cardinals Insider Names Breakout Reliever As 2026 Closer Candidate

Originally posted on St. Louis Cardinals on SI
By Curt Bishop | Last updated Sep 11, 2025 1:00 PM ET

The St. Louis Cardinals suffered a sweep at the hands of the Seattle Mariners this week and fell to 72-75 on the season. Their chances of reaching the postseason for the first time since 2022 have been all but squashed. Now, they are rebuilding and focusing on the future rather than contending. They were sellers at the trade deadline, getting rid of Ryan Helsley, Steven Matz and Phil Maton.

Because of those departures, competition has emerged for the closer spot. They need to find their new closer internally if they aren't going to spend money in free agency.

Though he blew a save on Wednesday night in Seattle, hard-throwing right-hander Riley O'Brien is an option, and Derrick Goold of the St. Louis Post-Dispatch presented a case for him to close in 2026.

Cardinals Insider Makes Case For Team's Next Closer

Jeff Curry-Imagn Images

"He has the stuff of late-game strikeouts.," Goold wrote.

"Now he has the opportunity of late-game moments.

And the Cardinals, much like their view of their lineup and outfield positions, are looking for who emerges in the closing weeks of this season as a candidate to compete for closing opportunities in 2026."

O'Brien has appeared in 34 games this year for St. Louis, going 3-0 with a 1.52 ERA and 1.5 WAR with three saves. He brings swing-and-miss capability to the back end of the Cardinals bullpen and has been one of the team's top relievers since the trade deadline.

Like Helsley, O'Brien can hit triple digits with his fastball. The Cardinals acquired him from the Mariners after the 2023 season when they went to work on addressing their pitching shortage. The team still has issues with the quantity of pitching.

But O'Brien can be trusted in high-leverage spots and has been able to close games for St. Louis this year since Helsley was traded. He may be the leading candidate to inherit the closer's role for the 2026 season due to his success in high-leverage spots and ability to hit triple digits.

The Cardinals have a lot of bullpen depth and can feel comfortable with some of the pieces they have acquired in recent years. O'Brien may be the best option to close with Helsley gone, unless the Cardinals go out and add a closer in free agency this winter.

It will be interesting to see if they decide to hand the reins over to him for next year.

This article first appeared on St. Louis Cardinals on SI and was syndicated with permission.

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