The attorney for George Zimmerman said he is "frustrated" that prosecutors withheld a color photo of the Florida gunman that could bolster his case that Zimmerman was being beaten when he shot Trayvon Martin.

The graphic photo of Zimmerman, taken the night of his fateful confrontation with Florida teen Trayvon Martin, shows the accused murderer with a bloody face. Zimmerman’s legal team released the photo, which was taken by police, after prosecutors substituted it in for a black and white photocopy that had been submitted earlier.

"I get frustrated when certain evidence gets out and other evidence is withheld," said Mark O'Mara, attorney for Zimmerman, 29, who faces murder charges in the Feb. 26 death of Martin, 17. "The photo is not a game-changer, but it is significant.

"If I had had that picture in my hand on April 11 ...," he said, referring to the date when Zimmerman was charged with second-degree murder.

Florida rules governing discovery require that original photos be submitted, but O'Mara says that the discovery phase has been rife with issues.

"It just seems like it's been pulling teeth for discovery in this case," he said. "This case is the opposite of any I've normally taken. Usually,discovery is dumped on your desk, because it's normally good for [the prosecution]. They usually try to shove it down your throat."

Martin was killed in a confrontation that sparked a national debate on race, guns and Florida’s controversial Stand Your Ground law, which states that people under attack do not have a duty to try to retreat before using deadly force.

Martin’s defenders say the youth was merely cutting through a gated community in Sanford, Fla., after picking up snacks during halftime of the NBA All-Star game when Zimmerman, a volunteer neighborhood watch captain, racially profiled him. Zimmerman claims the youth acted suspiciously, and attacked him, bashing his head against a sidewalk.

Zimmerman told investigators he grabbed his gun from a holster on his waist before Martin could get it, and shot the teenager once in the chest. A tape released by his lawyer shows two butterfly bandages on the back of Zimmerman's head and another on his nose.

Zimmerman’s lawyers said the photocopy of the image was provided by the prosecutors in the first round of discovery. The high-resolution digital file was finally provided to the defense on Oct. 29, and defense attorneys have said they will make all public documents related to the case available on their website.

Prosecutors had asked for the gag order, claiming a website and social media used by Zimmerman's attorney could influence potential jurors in the racially charged case.

Other experts questioned the withholding of the photo.

"This borders on prosecutorial misconduct," David Wohl, a criminal attorney and legal analyst said Tuesday during an interview on Fox News Channel.

On Monday, Zimmerman's defense team publicly released a motion, filed the same day, asking for the additional deposition of one of the lead investigators due to information that surfaced during his original interview on Nov. 19th.

Requests for comment to special prosecutor Angela Corey's office were not immediately returned.