AS HE LEFT the U.S. Attorney's Office in 2007, renowned mob prosecutor Barry Gross spiked the football - right in the faces of all the South Philly wiseguys he'd put behind bars.

"We defeated the mob," Gross proclaimed during a post-retirement interview with the Daily News.

Yesterday's sweeping indictment against reputed Philadelphia mob boss Joseph "Uncle Joe" Ligambi and 12 alleged associates is clear proof that Gross was wrong.

Or was he?

The Philadelphia faction of La Cosa Nostra is a shadow of its former self, eclipsed by the more sophisticated and creative Russian mafia and other underworld groups that profit from vice and scams.

And yesterday's announcement of the indictment of Ligambi's confidant, Anthony Staino Jr., and high-ranking members Marty Angelina, Joseph "Mousie" Massimino and George Borgesi, could cripple the organization.

The gambling, loan-sharking and extortion indictment - a 70-page snoozer that includes activity that's more than a decade old - may be a sign of how far the Philadelphia mob has fallen since the halcyon days of Angelo Bruno, whose tenure as boss ended in 1980 with a shotgun blast to his head.

"These guys just don't have the smarts for it," said Stephen LaPenta, a retired Philadelphia police lieutenant and organized-crime investigator. "They've reduced themselves to panhandlers."

There's nothing glorious about dealing with a busted bill-accepter on a video-poker machine, as detailed in the indictment: "Ah, espresso machine, no work too good," a shop owner allegedly told Staino in 2001, using coded language. "Every time I put the coffee in, it send it right back to me."

The charges do not include a single mob murder. Just threats, although law-enforcement sources said there could be more charges coming.

"It's really benign, in terms of acts of violence," said defense attorney Christopher Warren, who has represented Philly mobsters. "What the government accuses them of doing - gambling - is now being done by states to reduce their deficits. So, it's OK for Ed Rendell to do it to fund government programs, but if the boys in South Philly cover a few bets it's racketeering?"

John Apeldorn, former head of the Philadelphia police organized-crime and intelligence unit, said the mob might be wheezing from the latest indictment, but he doesn't expect it to die altogether.

"We've seen a 'dismantling' before," he said. "But if there's money to be made on the street, somebody will take the torch up. I still think there will be some activity, but nothing like years past."

So, who takes over if Ligambi and his top associates are convicted? And who would want to, given the fate of past Philly mob bosses?

"The tragedy here is that these guys just never seem to learn," Gross said yesterday. "The history is that you're going to be killed or incarcerated. It's astounding that people still get involved."

Former mob boss Joseph "Skinny Joey" Merlino, who is finishing his prison term in a Florida halfway house, has allies in Philly. But returning here would probably be a risky play.

"Ligambi seemed to have brought some stability," said John Maxwell, former chief of detectives for Philadelphia Police. "I think this is going to create some very uncertain times. You have to wonder what's next. How much is left?"