Puzzle pieces of the Trayvon Martin-George Zimmerman case are finally coming together. Multiple news sources are confirming that autopsy results show 17-year-old Martin had injuries to his knuckles when he died.

While Zimmerman's attorney, Mark O'Mara, wouldn't comment on the autopsy evidence, the findings seemingly confirm one part of the defense's story.

Zimmerman says that Martin threw the first punch, causing him to eventually opened fire in self-defense after his screams for help went unanswered.

After the shooting, Zimmerman told police that Martin rushed him after they exchanged words, knocked him to the ground and repeatedly hit his head against a concrete sidewalk.

After the fatal confrontation with Trayvon Martin, a medical report conducted by George Zimmerman's family doctor revealed the neighborhood watch volunteer to have a fractured nose, two black eyes and two lacerations on the back of the head.

Taken a day after Zimmerman's Feb. 26 altercation with Martin, the medical exam shows that Zimmerman suffered a closed fracture of his nose, according to two sources who have detailed knowledge of the investigation, cited by CNN.

As much as the story seems to fit, there could be another explanation for Martin's knuckle injury, according to Bill Sheaffer, a legal analyst with with WFTV.

It could be consistent with Trayvon either trying to get away or defend himself, Sheaffer told the news outlet.

The 28-year-old Zimmerman stands accused of fatally shooting Martin on Feb. 26 as the 17-year-old African-American teenager walked back to the Sanford, Fla., house where he was staying, after purchasing a bag of Skittles from a convenience store.

While Zimmerman is not denying the fact that he shot Martin, he sticking with his claim of self-defense and has entered a not guilty plea in the case.

Zimmerman's brother spoke of the medical reports in a March interview with CNN's Piers Morgan.

We're confident the medical records are going to explain all of George's medical history, Robert Zimmerman Jr. told Morgan. You return force with force when somebody assaults you. George was out of breath, he was barely conscious. George (would have been) dead if he had not acted decisively and instantaneously in that moment, he added.

On the opposition, representation for the Martin family has raised several questions about the Zimmerman medical report.

The family has very strong positions about this family physician's report that was done the next day, Benjamin Crump, the Martin family attorney, told CNN.

What we do know is on Feb. 26, the ER personnel did not believe his injuries were significant enough for him to go to the hospital. They didn't even put a Band-Aid on his head. That's important, he added.

Crum also commented on the autopsy, which revealed that Trayvon Martin had bloody knuckles on the night that he died.

He was fighting for his life, he told Anderson Cooper. Let's not forget that Trayvon Martin was fighting a man with a 9-millimeter gun. We also have to remember that he didn't start this fight. George Zimmerman got out his car and pursued Trayvon Martin.

Zimmerman had called 911 to complain about a suspicious person in the neighborhood on the night of the shooting, according to authorities.

The details of the call reveal that Zimmerman said he was following Martin after the teen started to run, prompting the dispatcher to tell him, We don't need you to do that.

The ensuing events would leave the 17-year-old Martin dead from a gun-shot wound to the chest.

Zimmerman faces a second-degree murder charge in the case, which has not yet been scheduled for trial.