Answer: Santino 'Sonny' Corleone (James Caan)
After the group decides Michael will kill both Captain McCluskey and mob boss Sollozzo, they wait to hear where a requested meeting will be held. When they do hear, Sonny asks, "Anybody know this joint?" Salvadore "Sally" Tessio (Abe Vigoda) says, "Yeah, sure, I do. It's perfect for us. A small family place, good food. Everyone minds his business. It's perfect. Pete, they got an old-fashion' toilet -- you know, the box, and - and - and - ah the chain-thing. We might be able to tape the gun behind it." When they agree to do this, Sonny says this quote and Clemenza assures him "The gun'll be there." In filming the assassination scene, Al Pacino badly injured his leg while escaping from the restaurant after the hit.