Assistant District Attorney John Gradel said Martinez faces a mandatory life term without parole for what he called "a particularly vicious, brutal attack."
Cazares-Olarte's wife, 31-year-old Delia Hernandez-Cortes, and the defendant's brother, 29-year-old Jose Martinez-Lopez, pleaded guilty in May to third-degree murder.
Defense attorney Frank Genovese said he expected the guilty verdict and didn't know whether an appeal would be filed.
Genovese had argued that even if jurors believed the prosecution's version of events, they shouldn't convict Martinez of first-degree murder.
"If one thing is clear, it's that my client never came up with the plan," Genovese said during closing arguments.
Gradel, however, said the defendant brought along a gun, which showed an intent to kill, and while another man held the victim at gunpoint, Martinez went outside and got the rock.
"He hit him six times," Gardel said. "Does it get any clearer?"