The Giants optioned Whisenhunt to Triple-A Sacramento on Tuesday, Alex Pavlovic of NBC Sports Bay Area reports.
Whisenhunt coughed up three runs in four frames during his start Saturday, elevating his ERA to 5.02 through 14.1 MLB innings. He'll now lose his place on the active roster to make room for Tyler Fitzgerald, who was recalled from Triple-A to provide additional bench depth. Landen Roupp (elbow) is nearing activation from the injured list and is the likely candidate to fill the open spot in San Francisco's starting rotation.