Tuhia he haere tonu mō tēnei wāhanga - I te tau 2011, i tīmata te mahi a Grilli hei kaitākaro āwhina ki 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 eke a Grilli ki tana kapa All-Star tuatahi
I riro ia hei kaitiaki o Pittsburgh i te tau e 36. 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.