Chicago Cubs shortstop Javy Baez has a hairline fracture in his left thumb, an MRI on Saturday revealed.
Baez will see a hand specialist on Monday, at which point a timeline for his return will be determined.
The shortstop missed his fifth straight game Saturday at the Milwaukee Brewers due to the injury. He hurt the thumb sliding headfirst into second base during last Sunday's game against the Brewers at Wrigley Field.
Baez is hitting .281 with 29 home runs and 85 RBIs for a Cubs team that entered Saturday holding the second spot in the NL wild card race, 2 games behind the Nationals and 3½ games ahead of the Diamondbacks. The Cubs are 2½ games behind the first-place Cardinals in the NL Central.
ESPN's Jesse Rogers contributed to this report.