Alexander was removed from Sunday's game against the Dodgers due to left hamstring discomfort, Susan Slusser of the San Francisco Chronicle reports.
Alexander exited Sunday's matchup after being examined by a trainer in the bottom of the ninth inning, and he's dealing with a hamstring issue that has plagued him recently. It's unclear whether he'll require a trip to the injured list, but he should be considered day-to-day for now.