"His hamstring started getting tight [Saturday]," Pirates manager John Russe'l said. "And it just continued to get tight. We'll see how he is Tuesday."
LaRoche has been one of the Pirates' hottest hitters in the second half of the season. The veteran ranks third with 22 RBIs behind Philadelphia's Ryan Howard (27) and Los Angeles' Manny Ramirez (24) in the month of September.
Todd Krise is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.