Kammala jumla mai zuwa: Romo ya yi kyau sosai don fara kakar 2012 kuma bai ba da izinin samun nasara ba har zuwa ranar 17 ga Mayu, 2012. Bayan Brian Wilson ya yi aikin Tommy John a watan Afrilu, Santiago Casilla ya ba da rawar da ya fi kusa. Casilla ya sauya 20 daga cikin damarsa na farko na 21 amma ya busa biyar daga cikin sauye-sauye tara na gaba, yana aikawa da 7.71 ERA daga Yuni 23 zuwa Agusta 7. Bochy ya sanar a ranar 7 ga watan Agusta cewa Giants za su yi amfani da dabarun "bullpen ta kwamitin", tare da Romo, Javier López, da Jeremy Affeldt suna jefa wasannin biyu na ƙarshe na wasannin kusa, dangane da waɗancan masu bugun za su fuskanta. Romo da López sun sami mafi yawan damar ceto; Affeldt kawai yana da ceto bayan wannan lokacin. Daga wannan lokacin har zuwa ƙarshen kakar, Romo ya canza tara daga cikin tara ya sami damar ceto kuma ya buga 1.33 ERA. Romo ya bayyana a wasanni 69 na kakar 2012, ya sami ceto 14 tare da 1.79 ERA, wanda shine na huɗu a cikin masu taimakawa na NL kuma ya bi kawai Craig Kimbrel (1.01), Aroldis Chapman (1.51) da Eric O'Flaherty (1.73). Kodayake ya zama mafi kusa a ƙarshen shekara, ya sami lambar yabo ta Gibby don kasancewa MLB's Setup Man of the Year. Giants sun lashe NL West; a cikin NLDS da Cincinnati Reds, Romo ya bayyana a wasanni uku, ya lashe Game 3 kuma ya ceci Game 5. Ya jefa a duk hudu na Giants 'lashe a cikin
NLCS da St. Louis Cardinals amma ba su sami damar ceto ba. Koyaya, a cikin Wasannin Duniya da Detroit Tigers, ya yi wasanni uku kuma ya yi rikodin ceto a kowane ɗayansu. Ya buga wasan karshe na wasan yanke hukunci na 4 kuma ya buga uku a jere, gami da Miguel Cabrera don fitarwa ta ƙarshe da nasarar Giants. A gasar cin kofin duniya, Romo ya jefa kwallaye uku cikakke kuma yana da strikeouts biyar.