Michael Vick is taking responsibility for his actions, the NFL football star said in an interview Sunday night.
"The first day I walked into prison and they slammed that door, I knew the magnitude of the decisions that I make and the poor judgment and what I allowed to happen to the animals," Vick said on "60 Minutes."
Vick, 29, was convicted of conspiracy and running a dog-fighting organization in August 2007 and served 18 months in prison. The former quarterback for the Atlanta Falcons was once the highest paid player in the NFL. The Philadelphia Eagles signed Vick to a contract last week.
"There is no way of explaining the hurt and the guilt that I felt," he said. "And that was the reason I cried so many nights."
But forgiveness may not come so easily, judging by protestors at Eagles' practices this weekend holding up signs reading things like "Hide Your Beagle, Vick's an Eagle."
Vick was convicted for training dogs in death matches and killing the ones that underperformed by shooting, drowning, hanging and electrocution.
Many of Vick's former dogs are still being rehabilitated. The toughest cases were brought to the Best Friends Animal Sanctuary in Utah.
Among them were Georgia, her body scarred from fighting, and Cherry, used as a bait dog, who is now terrified of people.
But through positive reinforcement, dedicated trainers are able to slowly draw out these abused animals, animals they say are worth saving.
"I personally believe that every one of them is going to find a great home or, if need be, we will take care of them the rest of their lives," trainer John Garcia said.
Gender Divide: Should Vick Have Been Allowed to Play Again?
Michael Vick says he now wants to help bring awareness to animal cruelty and is working with the Humane Society.
But whether it will it be enough to rehabilitate his reputation remains to be seen.
A divide has emerged between men and women on whether the NFL should have allowed a convicted felon to return to the game, according to one poll.
Thirty-nine percent of women, compared to 69 percent of men, agreed with the NFL's decision to allow Vick to return to the sport, according to a recent Marist poll.
More than half of the women polled said they disagreed with the NFL commissioner's decision to allow Vick to play, compared to only 27 percent of men.
One woman posted a note on the Web site sackvick.net , which has tried to organize a campaign to "Sack Michael Vick," explaining her reasons for boycotting the NFL.
"Vick has accepted and served the punishment that society deemed appropriate for his acts," Vicki wrote. "I agree that he should be allowed to live his life in peace. HOWEVER, playing in the NFL is a privilage [sic], and he has lost his right to that privilage [sic]. He can work hard like the rest of us to support himself, but he DOES NOT deserve millions and the status of celebrity and role model."
The Eagles signed Vick to a one-year, $1.6 million contract, with a $5.2 million team option for a second year.
Animal lovers are also divided in their reaction.
"Now that he has a contract to resume a very visible career in the public eye -- a lucrative career that few people ever have the chance to experience even once, let alone a second time, after committing a horrific and inhumane crime -- it's time for Michael Vick to demonstrate he can change and be a force for good," Marie Belew Wheatley, president and CEO of the American Humane Association, said in a statement. "In particular, we hope he can become a positive role model for young people and that, in light of the incredible second chance he has been given, he now proves himself truly worthy and humane."
But People for the Ethical Treatment of Animals (PETA) has said it remains skeptical.
The Associated Press contributed to this report.