"When I went into second base, I kind of hesitated a little bit in my slide," he said. "It felt more like a cramp when I did it, but my third at-bat when I took that swing, I felt it. It bit pretty good. It hurts."
Blum left after the sixth inning and was replaced at third base by rookie Edwin Maysonet. The veteran infielder's status is currently day-to-day.
"We'll wake up tomorrow and see how it goes, and I'll probably have a better evaluation of what's going on," Blum said. "[Athletic trainers] Nate [Lucero] and Rex [Jones] are going to do a good job in taking care of me, and hopefully it is just a day-to-day thing and something I can deal with and work through."
Blum said he hasn't pulled a hamstring since 1996, while playing for the Expos' Double-A affiliate in Harrisburg, Pa.
Alyson Footer is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.