Heyward, who was playing center field for the Cubs on Thursday night, barely missed the ball off the bat of Freddie Freeman, and was forced to exit the contest due to tightness in his right hamstring.
After the game, Cubs manager Joe Maddon said that there is no timetable for Heyward's return, but ruled him out for the team's next few games against the Philadelphia Phillies.
If Heyward is forced to go on the disabled list, it would be a blow to a Cubs team that is slowly getting healthy again. Third baseman Kris Bryant just finished a rehab stint in Iowa, and pitcher Mike Montgomery returned for Thursday's game against the Braves.
Rosters expand to 40 players on Saturday, meaning that the Cubs could wait an extra day and not have to remove anyone from their 25-man roster to replace Heyward.