Manager Dave Martinez said Guerra's hamstring "grabbed him pretty good" during his appearance Tuesday against the Phillies, Mark Zuckerman of reports.

Martinez indicated the injury occurred on the right-hander's final pitch, but he struggled with his control throughout the appearance, throwing only 14 of his 30 pitches for strikes. He had two strikeouts and three walks over 1.2 scoreless innings without giving up a hit. Guerra wasn't provided a timeline for his return and should be considered day-to-day until he undergoes further evaluation.

More News