Cardinals closer candidate's injury could have multiple depressing implications

When news emerges about players right before spring training, it's rarely positive, and for the St. Louis Cardinals, it's come in the form of injuries to pitchers, both those in the farm system and ones expected to contribute to the big-league bullpen. The Cardinals recently announced that minor league prospects Ixan Henderson and Brandon Clarke have been shelved with a flexor strain and a shoulder aneurysm, respectively, and now a leading candidate to serve as the Cardinals closer has been sidelined with a calf strain.

Riley O'Brien's injury could have a few repercussions.

O'Brien sustained the injury while throwing a live bullpen session on Feb. 14, and while it isn't expected to keep him out for an extended period, it will prevent him from pitching for Team Korea in the World Baseball Classic. According to O'Brien, the series would have meant a lot to him had he been able to participate in it, as his family had already made plans to watch him serve as the closer for the squad.

Outside of the World Baseball Classic, O'Brien's injury could lead to his falling behind in the battle for the Cardinals' closer role. O'Brien received his first extended major league look in 2025, and he ran with the opportunity, pitching to a 2.06 ERA in 48 innings and notching six saves. Given his success, O'Brien appeared to have the inside track to closing in 2026, but if the injury keeps him out for some or all of spring training, it is unlikely that the Cardinals will tab him as their closer until he ramps back up.

O'Brien's potential absence would open the door for other pitchers to receive closing opportunites. The favorite would likely be JoJo Romero, whom many fans expected to be traded in the offseason but who ultimately stayed put. Left-handed closers aren't too common around the league given their importance in other game situations, such as facing lefty-heavy spots in a lineup, but Romero's 2.07 ERA and eight saves last season could qualify him for the role regardless, at least until the trade deadline if the Cardinals decide to move him then.

Matt Svanson would serve as a more traditional closing option in O'Brien's absence, and given his relative youth (he just turned 27), he could become the Cardinals closer for the next several seasons after finishing his rookie year with a strong 1.94 ERA and 68 strikeouts in 60.1 innings.

At 31 years old, O'Brien isn't a spring chicken and thus, unlike Svanson, probably isn't a major part of the Cardinals' future. The rebuilding Cardinals are likely to carry out more moves at the trade deadline and could look to deal O'Brien as well as Romero. However, a long-term injury would throw a large wrench into those plans and cause his value to plummet.

The Cardinals aren't likely to have a plethora of save opportunities in 2026, but O'Brien's potential absence could result in some ramifications for the team in terms of its roster and any possible returns if the Cardinals want to flip him at the deadline. Hopefully the injury isn't one that lingers and O'Brien can get in a full or nearly full spring training and the Cardinals can insert him as their stopper on day 1.