Alexander (hamstring) will likely require a trip to the injured list, Andrew Baggarly of The Athletic reports.
Alexander exited Sunday's game against the Dodgers with left hamstring discomfort, an issue he's been dealing with for some time. He'll presumably be re-evaluated Monday before the Giants officially determine whether he'll require an IL stint, but Sean Hjelle was scratched from his minor-league start Sunday and is a candidate to be called up if Alexander is sidelined.