The prosecution in the first-degree murder trial of former Harvard graduate student Alexander Pring-Wilson offered crucial evidence yesterday—a tape of the 911 telephone call placed by the defendant on the night of the alleged murder.

Pring-Wilson, a former student in the Russian and Slavic Studies Department, is facing life in prison for allegedly stabbing Michael D. Colono during a fight outside Pizza Ring on Western Ave. in April 2003.

In the 911 telephone call, which Pring-Wilson made at 12:59 a.m., only minutes after the victim left the crime scene, Pring-Wilson appears to lie to the police about whether he was involved in an altercation with Colono.

During the taped conversation, played for the jury in Middlesex Superior Court, Pring-Wilson told police that he had just witnessed a stabbing and that the perpetrators had “fucking run off.” Pring-Wilson sounded out of breath and occasionally slurred his speech. Previous testimony in the trial, which began Monday, revealed that Pring-Wilson consumed several drinks earlier that night while bar-hopping.

“Is the patient still there with you?” the 911 dispatcher, Michael Ferraro—who also testified today—asked Pring-Wilson.

“No sir, I just saw it happen sir. I’m just a fucking bystander, sir,” Pring-Wilson said.

“Did you see who did it?” Ferraro asked.

“No sir, it was just some guy,” the defendant said.

When Ferraro asked Pring-Wilson whether the suspect was white, black or Hispanic, Pring-Wilson answered, “No, not really.”

Yesterday was day three of the trial, which is expected to last a month. So far, the prosecution and the defense have each offered a different version of the events that led up to the stabbing.

Assistant District Attorney Adrienne Lynch argued during opening statements Monday that Pring-Wilson was walking by the parked car where the 18-year-old Colono sat with his cousin, Samuel Rodriguez, and Rodriguez’s girlfriend, Giselle Abreu, while they were waiting for their pizza order.

Lynch said that after Colono called attention to Pring-Wilson’s stumbling, the two had a heated exchange which ended in Pring-Wilson opening the door of the car and stabbing Colono five times.

But Pring-Wilson’s attorneys claim that he acted in self-defense after he was attacked by Colono and Rodriguez. They hold that Colono, not the defendant, opened the door of his car and threw the first punch.

On Tuesday, Rodriguez testified to seeing Pring-Wilson holding a knife, and the defense sought to undermine Rodriguez’s credibility, forcing him to revise the account of the fight he had presented in pre-trial hearings.

Defense witness Julie Ann Sitler, who called 911 after seeing Rodriguez, Abreu and the wounded Colono pull up to a 7-Eleven after the stabbing, said yesterday that Rodriguez pulled Colono out of the car onto the sidewalk in an attempt to revive him.

Pring-Wilson attorney E. Peter Parker attempted to establish that Colono and Abreu were not cooperating with the police who showed up at the 7-Eleven.

At the time, both Abreu and Rodriguez did not hold valid driver’s licenses, and Rodriguez testified Tuesday that he feared “getting in trouble” with the police.

Parker asked Sitler if Rodriguez told Abreu, “We gotta go. We gotta go.” Sitler answered that he did.

“They were ignoring the police officers?” Parker questioned Sitler. “They weren’t giving answers to the police?”

“No,” Sitler answered.

Another defense witness, Officer Robert Disario of the Brookline Police Department, said that “initially [Rodriguez] was very uncooperative. He was vague.”

Mark Brinkman, the EMS officer who responded to the scene at the 7-Eleven, testified yesterday that he arrived at the scene at 2 a.m., about an hour after the stabbing. He said that Colono, a lifetime Cambridge resident and father to a three-year-old daughter, was conscious but “not oriented” and not able to answer any questions.

—Robin M. Peguero contributed to the reporting of this article. —Staff writer May Habib can be reached at habib@fas.harvard.edu.