(CNN) -- A court hearing in Philadelphia took an unforeseen turn when a witness, testifying about the consequences of losing his left eye in an alleged assault, began crying and his prosthetic eyeball popped out of its socket and into his hand, unsettling the jury and resulting in a mistrial, according to attorneys involved.
"I've been a prosecutor for 26 years and I've never seen anything like that happen. It was unusual; it was shocking," said Philadelphia Assistant District Attorney Mark Gilson, who is prosecuting Mathew Brunelli, 23, charged with aggravated assault, for allegedly stabbing John Huttick in the eye during a bar fight in August 2011.
The eye had to be surgically removed, Gilson said.
"He was crying, and when it came out, he caught in his hand and just held it there," said defense attorney Eileen J. Hurley, "It was a shocking event to witness."
"Two jurors visibly gasped and jumped up like they were getting out of their seats," Hurley said.
"The judge had to call recess and let everyone take a breath," Gilson added.
Hurley said after the recess, she felt the trial couldn't go on because the event could generate extra sympathy for Huttick, prejudicing the jury against Brunelli.
"A bell like that can't be unrung," Hurley said.
Judge Robert P. Coleman granted Hurley's request for a mistrial.
"Let's face it; it was no secret. The evidence shows the victim was stabbed in the eye. There is medical testimony. Everyone knew (Huttick) has a prosthetic eye," said Gilson. "I don't think it was enough to declare a mistrial, but it's at the discretion of the judge, so we have to start over."
Hurley contends her client didn't stab anyone.
"My client was trying to defend himself and his girlfriend and trying to leave," she said, noting that Huttick is much taller and weighs much more than Brunelli.
"He was not arrested that night, and criminal charges weren't filed until months later when (Huttick) filed a civil suit against my client," she added. "We have an expert that will say it was just a fist."
"The issue is settled; he admitted he punched the victim and caused the injuries, but claims there was no weapon," said Gilson, "That's just unbelievable. The man's eye had a puncture wound. That's not a punch."
The case is set to be retried March 4.