Whakaotihia te rerenga e whai ake nei: I te tau 2011, i tiimata te mahi a Grilli hei kaitakaro awhina me te Pittsburgh Pirates. I taua tau, i kawea e ia te 2.48 toharite whiwhinga (ERA) me te 10.2 nga whiwhinga mo ia iwa (K / 9) i roto i te 32 nga whiwhinga i tukuna (IP), ka pai ake i te tau 2012, i te wa i piki ake ai tana reanga whiwhinga ki te 13.8. I te tau 2013, i hanga e Grilli tana tuatahi
Ko te kapa All-Star, ā, ko ia te kai-whakataunga o Pittsburgh i te 36 o ōna tau. Mai i te 2011 ki te 2014, i whakahiatohia e ia he 3.09 ERA me te 11.9 K / 9, 3.3 BB / 9 me te 34.2 ōrau o te reanga o te whenua i roto i te IP.