Texas Rangers shortstop Corey Seager had an appendectomy on Thursday after experiencing abdominal pain during a game the previous night.
Chris Young, the team's president of baseball operations, said Seager had surgery in Texas after the team had traveled to California for the start of a series against the Athletics on Friday night.
Young said it was too early to know how much time the two-time World Series MVP will miss.
Seager will be placed on the 10-day injured list and the Rangers will call up utility player Dylan Moore, who had just been signed to a minor league contract after being released by AL West rival Seattle.