Manager Dave Martinez said that Gallo pulled his left hamstring during Tuesday's 5-4 win over the Tigers, Andrew Golden of The Washington Post reports. Gallo went 1-for-3 with a run scored prior to his departure from the game.
Gallo was grabbing at his hamstring after grounding out in the seventh inning, and he was immediately replaced at first base by Joey Meneses. Martinez said the Nationals will know more about the severity of Gallo's injury Wednesday, but the team will likely bring a minor-leaguer onto its taxi squad in case he needs to go on the injured list.