The St. Louis Cardinals made significant moves at the trade deadline, sending away three relief pitchers whose contracts were about to expire. Phil Maton was traded to the Texas Rangers, Steven Matz went to the Boston Red Sox, and most notably, Ryan Helsley was dealt to the New York Mets. Helsley’s departure struck a heavy blow to the Cardinals’ bullpen, as he had established himself as one of the team’s top closers in recent years.

Despite these losses, the Cardinals are starting to look within their own ranks to fill the void left by Helsley. One player gaining attention for potentially stepping into the closer role is Riley O’Brien, who has impressed while pitching late in games.

Riley O’Brien’s Rise as a Late-Inning Relief Option

Reliever Riley O’Brien has quietly become one of the Cardinals’ more reliable bullpen arms over recent weeks. According to Redbird Rants writer Scott Plaza, O’Brien has delivered some of his best performances in the critical late innings. Plaza noted,

“Also encouraging is the fact that he has performed his best late in the game. In the eighth inning or later, he has thrown 13.2 innings, striking out 10 and allowing just two runs,”

—Scott Plaza, Redbird Rants.

Although O’Brien still struggles with command at times, he has shown clear progress, walking only three batters in his last 6.2 innings across seven appearances. Manager Oliver Marmol has yet to name a definitive closer as the season progresses, but O’Brien is increasingly seen as a strong candidate to take on that responsibility.

Competition Within the Cardinals’ Bullpen for Closer Role

JoJo Romero, the only left-handed reliever in the Cardinals’ bullpen, has been used mainly in high-leverage, matchup-specific situations. Plaza commented on the bullpen landscape, saying,

“JoJo Romero seemed likely to get some chances, but he is the only lefty in the bullpen, so he is still used in high-leverage matchup opportunities. If O’Brien can keep his momentum going through August, there’s little reason to believe he won’t become a favorite for the closer role in September and beyond.”

—Scott Plaza, Redbird Rants.

O’Brien’s electric arm and sharp slider have been vital for the Cardinals, particularly as the team navigates the loss of Helsley and other bullpen veterans. His strong outings have helped the Cardinals remain competitive in the National League despite their recent roster shakeup.

Potential Questions About O’Brien’s Fit as Long-Term Closer

Despite his recent success, some doubt remains about whether Riley O’Brien is the ideal long-term replacement for Ryan Helsley. At 30 years old, O’Brien does not have an extensive track record as a major league closer. The Cardinals may also explore free agency or promote a prospect from their farm system to fill the closer role in the future.

Still, with the current state of the bullpen, O’Brien’s performance has kept the Cardinals afloat during a challenging stretch, providing hope that he can handle the pressure of closing games as the team pushes toward the postseason.

Looking Ahead: What the Closer Role Means for the Cardinals’ Season

As the Cardinals move forward without one of their premier bullpen arms, the choice of a new closer will be pivotal to the team’s success in the final part of the season. Riley O’Brien’s recent emergence offers the team a viable internal option, but the decision remains open as the roster continues to evolve. How the Cardinals manage their bullpen roles will be critical as they aim to stay competitive in the National League and return to postseason contention.