Australian baseball player Chris Lane suffered such catastrophic gun shot injuries only a miracle could have saved him, the forensic pathologist who performed his autopsy told an Oklahoma court.
Dr Inis Yacoub was one of the final prosecution witnesses in the three-day first-degree murder trial of 17-year-old Chancey Luna in the Stephens County Courthouse.
Luna's lawyer Jim Berry has told the jury Luna fired the .22 revolver from a high school mate's moving Ford Focus to scare Lane, who was jogging along a residential street in the rural Oklahoma city of Duncan on August 16, 2013.
The bullet struck 22-year-old Lane in the back and ricocheted off ribs, punctured both lungs and tore his aorta and pulmonary artery.
Dr Yacoub said blood was found in Lane's airways, indicating he would have been gasping for breath before he died.
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It corroborated two other witnesses at the trial who tried but failed to resuscitate the dying Australian at the side of the road.
District Attorney Jason Hicks asked Dr Yacoub if Lane received immediate medical attention would he have survived.
"Apart from a miracle, no," she replied during Thursday's testimony.
Lane's parents Peter and Donna, who flew in from Melbourne, and other family and friends wept during the graphic testimony.
Hicks and Berry will deliver their closing addresses to the jury on Friday (Saturday AEST).
If the jury finds Luna guilty of first-degree murder he could be sentenced to life in prison without the prospect of parole.
It is believed Berry will ask the judge to let the jury consider a second-degree murder charge.
Berry, who called just one defence witness, Luna's mother Jennifer who spent less than five minutes in the witness box, has played down the "small calibre" bullet fired at Lane.
Dr Yacoub, however, said Lane lost one-third of his blood and the bullet "perforated major organs".
"That's damage to vital organs that could not be reversed," she said.
Lane, who played for the Essendon Baseball Club, had a scholarship at Oklahoma's East Central University and was dating Duncan local Sarah Harper.
