But the response from people dismayed about his return was just as sudden.
Vick was introduced by the Eagles on Friday after signing a one-year deal for $1.625 million, with a team option for a second year at $5.25 million.
According to sources, the first-year salary will be paid regardless of any length of a ban imposed by NFL commissioner Roger Goodell, ESPN senior analyst Chris Mortensen reported, unless the Eagles release him before the opening game.
A Web site, sackvick.net, quickly sought protesters to contact the Eagles' corporate sponsors, and it had posted many of them and their CEOs with e-mail addresses and phone numbers, from PepsiCo and Sprint Nextel to Lincoln Financial.
Philadelphia native Jan Garber spent Friday morning calling Eagles sponsors after finding them on the team's Web site, according to The Philadelphia Inquirer.
"This is my own campaign; the corporate sponsors are on the Eagles' Web site," Garber said in an e-mail to the newspaper. "I am not an Eagles fan, just a native Philadelphian who is shocked and dismayed by this clandestine signing of a criminal to the local franchise.
"This maneuvering smacks of, 'The fans will have to accept it. They'll get over it. Think of the publicity! We'll make millions more this season.' "
She was successful in contacting several of the sponsors, but told The Inquirer "only Budweiser said anything of substance" and declined to elaborate.
"The others pretty much washed their hands of the matter by saying they have no part in the Eagles' management decisions," said Garber, who contacted The Inquirer about her part in the protest.
As a board member for the Pennsylvania Society for the Prevention of Cruelty to Animals, Jennifer Utley, the wife of Philadelphia Phillies second baseman Chase Utley,was among a group of protesters who stood outside the Eagles' practice facility Friday as the team introduced Vick during a news conference inside.
"We fight animal cruelty every single day in this city," Utley told Fox 29 of Philadelphia.
She said her organization was taken aback that no one from the Eagles contacted it during their process of deciding whether to sign Vick.
"I think if you're planning on being conscious of a very sensitive issue, it might be positive to do that," Utley said.
Meanwhile, Reebok, the official uniform supplier for the NFL, offered replica "VICK 7" jerseys on the NFL and Eagles' Web sites, two years after it had suspended sales of Vick's Atlanta Falcons jerseys before he faced charges of conspiracy and running a dogfighting operation.
"They've already seen the demand," Reebok spokesman Dan Sarro said of retail outlets that sell NFL jerseys, according to The Inquirer. "We've already met the minimums. So we will go into production."
Former Eagles quarterback Ron Jaworksi, an ESPN analyst for "Monday Night Football," told the newspaper he was fine with the team's passing on the No. 7 jersey to Vick, who has worn the number throughout his football career.
"I have absolutely no problem with it," Jaworski said.
Two local sporting good stores would be stocking the Vick jerseys as early as Saturday, the paper reported, citing a Modell's spokesman.
Even homemade T-shirts had begun to surface on eBay. Some featured fronts that read "Forgive Vick, Go Eagles" and "Hide Your Beagles, Vick's An Eagle," The Inquirer reported.
At Electronic Arts on Friday, as it launched its popular "Madden NFL," plans were already under way to add Vick to the video game's lineup by Wednesday.
"Couldn't he have just given us just one more day?" EA spokesman Rob Semsey said of his reaction to Vick's agreement Thursday, according to the Los Angeles Times.
Vick participated in his first practice in Philadelphia on Saturday, running the scout-team offense in a morning walkthrough. He was expected to do more when the team returned to the field in the afternoon.
Eagles coach Andy Reid says Vick definitely is in shape enough to handle practice and the team will bring him along accordingly.
For their part, the Eagles sent a statement to their suiteholders, or "premium-service clients," telling them the decision to sign Vick "may result in some personal soul-searching for you, along with some public debate in the coming days and weeks.
"We do not want this to distract from the relationship we have with you," the Eagles' statement said. "And we remain fully committed in putting the highest-quality product on the field and delivering wins to Eagles fans."
Vick expressed remorse Friday at the news conference.
"I know I've done some terrible things, made a horrible mistake. Now I want to be part of the solution and not the problem," Vick said Friday, referring to his conviction for his role in running a dogfighting ring.
The Eagles' statement said the team didn't take the weight of their potential decision lightly.
"The ultimate decision upon us was this," the statement said. "If a person made a terrible mistake and then paid their debts to society, was deeply remorseful and turned their life around completely, and not only lives a life or virtue themselves but is investing time to make sure others don't make the same mistakes, would you be willing to help this human being move forward? Would you give them a second chance?"
Information from ESPN senior NFL analyst Chris Mortensen and The Associated Press was used in this report.