Grilli wrote Sunday on his Twitter account (@grillcheese49): "This Italian Stallion is FIRED UP about the City of Brotherly Love! Balboa workouts paid off and READY TO GO!!!"
Grilli is 18-18 with a 4.74 ERA in 238 appearances over eight seasons in the big leagues. He last pitched with the Rockies and Rangers in 2009, when he went a combined 2-3 with a 5.32 ERA in 52 appearances.
He did not pitch last year because of a knee injury.
Grilli will not be in big league camp, which begins Feb. 14 in Clearwater, Fla. He will be in Minor League camp.
Todd Zolecki is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.