The knife used was reported to have been about 4 to 5 inches long. It sliced through the cartilage in the sixth rib, through the heart sac and into the left ventricle of the heart, according to the doctor who did the autopsy.
He said the toxicology report showed no alcohol in De La Cruz's blood but traces of methamphetamine were found.
El Centro police detectives and officers also testified Friday on what they encountered when they arrived at the scene of the incident.
The stabbing occurred after De La Cruz and Serrato got into a scuffle. What the scuffle was about is a matter of dispute between Serrato's attorney, Eduardo Rivera of Calexico, and Imperial County Deputy District Attorney Susana Salgado.
Salgado said during her opening statement Thursday the stabbing happened after the two got into a fight over a comment Serrato made prior to the incident.
Rivera said during his opening statements De La Cruz initiated the fight by punching Serrato three times with an object in his hand. Rivera said he doesn't know what the object was but it caused a large gash on Serrato's forehead. Serrato, fearing for his life, stabbed Rivera in self-defense.
Rivera claimed De La Cruz initiated the fight over a bicycle De La Cruz allegedly stole. According to Rivera, earlier that morning De La Cruz stole the bicycle and sold it to Manuel Vasquez, who lives on the block where the incident occurred.
Serrato was at Vasquez's home talking to him when De La Cruz arrived. De La Cruz reportedly became angry when he saw Serrato in possession of the bicycle, Rivera said.
De La Cruz, a Harbor City resident who had lived in El Centro and had returned to visit relatives, had a record of being arrested for petty thefts. He had methamphetamine in his possession when he was killed.
Serrato had been convicted of three felonies and served time in prison and was on parole at the time of the stabbing.
The trial will reconvene Tuesday morning.
>> Staff Writer Mario Rentería can be reached at 337-3441.