Riley O’Brien’s WBC Participation in Doubt Due to Calf Injury

St. Louis Cardinals reliever Riley O’Brien is facing uncertainty regarding his participation in the upcoming World Baseball Classic (WBC) due to a calf injury, potentially dealing a significant blow to the Korean national team’s bullpen plans.

Injury Details and Team Response

Reporter Daniel Guerrero of the St. Louis Post-Dispatch reported on February 18, 2026, that O’Brien is experiencing pain in his calf . The St. Louis Cardinals are currently evaluating the extent of the injury, with an official announcement expected soon.

O’Brien’s Role with the Korean National Team

O’Brien, who was named Korea’s closer for the WBC on February 6, 2026 , was expected to be a key component of the team’s bullpen. His selection was made possible by the WBC’s eligibility rules, which allow players to represent a country based on their ancestry. O’Brien qualifies through his Korean mother.

Impact on the Korean Team

The potential loss of O’Brien comes at a challenging time for the Korean national team. Manager Ryu Ji-hyun is already dealing with injuries to starting pitchers Moon Dong-ju and Won Tae-in, weakening the team’s starting rotation . O’Brien’s absence would further disrupt Ryu’s plans to build a dominant bullpen.

O’Brien’s Recent Performance

O’Brien, 31, had a strong 2025 season with the St. Louis Cardinals, appearing in 42 games with a 3-1 record, 6 saves, and a 2.06 ERA . He was anticipated to be a crucial closing pitcher for the Korean team.

Other Half-Korean Players on the Roster

O’Brien is one of four players with Korean heritage selected for the national team, including Detroit Tigers outfielder Jahmai Jones, Houston Astros utility player Shay Whitcomb, and Seattle Mariners pitcher Dane Dunning .