Marvel Team-Up, Vol. 1 #14 (1973)

Spider-Man and The Savage Sub-Mariner: Mayhem is the Men-Fish!
Spider-Man is ready to stop a mugging, but the intended victim is Namor, the Sub-Mariner, the Avenging Son, and quite capable of handling himself. Peter tries to restrain Subby, and realizes his actions allowed a killer to escape. Wishing to make up for it, he agrees to help Namor pursue Tiger Shark for the betterment of the world.
Release Date: 1973