The Progress Club in Rockville is giving up its massive effort to fight illegal gambling charges, club sources said yesterday.

Under a plea bargaining agreement being hammered out with Montgomery County prosecutors, the corporation that runs the exclusive 500-member club will enter a plea of no contest later this month to one charge of running a place to gamble in violation of Maryland law, thus averting a second trial.

Last December, Montgomery Circuit Court Judge William Miller declared a mistrial after a jury told him that it was too torn by questions of fact and law to judge the Progress Club Inc., despite a high-profile, four-day trial.

Miller's declaration left Progress Club members and prosecutors unable to claim a victory. Both sides vowed to continue the fight.

The no contest plea apparently will satisfy both the club's mostly wealthy members who see nothing wrong with playing cards and police and prosecutors who aggressively pursued criminal charges against the club.

The plea of no contest "is, number one, not an admission of guilt and number two, has the legal effect of being a plea tantamount to guilty -- it's both sides of the same coin," said a Montgomery Circuit Court judge who requested anonymity.

Sources said that under the plea bargaining agreement, some portion of the $22,000 seized by police during a raid in June would be forfeited.

In addition, the club must pay a $500 fine and be on probation for 18 months.

Rockville police also would make periodic "unannounced" visits to the club and examine the club books, according to some sources familiar with the agreement.

States' Attorney Andrew L. Sonner refused through a spokeswoman to comment yesterday, saying such comments would violate professional ethics.

But Alan J. Goldstein, an attorney for the club, said under the terms of the agreement the corporation will busy itself with social and charitable activities instead of fostering the widespread card playing that has netted the club millions of dollars since it was founded in 1917.

But sources said club members are likely to continue playing cards in informal groups such as those at country clubs and in private homes.

"The club is going to get out of the business of participating in any gambling that goes on there," Goldstein said yesterday. "If the individual men are going to play cards the club is not going to be involved in that activity on an institutional basis."

Over a 28-month period, club members risked $2.54 million on poker games, according to Rockville police. Members paid the club $12 to play poker and $9 to play gin rummy and $3 for a deck of cards, according to testimony given in court.

One of the main features of the agreement, and its biggest "sticking point," according to sources, is a public statement to be made by a club spokesman when the agreement is announced at a March 29 press conference.

The statement has been described by some sources as an admission of the club's wrongdoing and by others as a compromise between admitting guilt and denying it.