Despite a last-ditch offer to keep the NFL Cardinals in St. Louis, Maryland Stadium Authority chairman Herb Belgrad said yesterday he remains confident that team owner Bill Bidwill will move his team to Baltimore next season.

"It's not a false optimism," Belgrad said yesterday. "I know what my product is."

Bidwill, whose family has owned the Cardinals 52 years, including the last 27 in St. Louis, has been noncommittal about whether he intends to move the team and, if so, where. An employe said yesterday Bidwill has not discussed his intentions with anyone in the organization, including one of Bidwill's sons.

Missouri Gov. John Ashcroft and Charles F. Knight, president of Emerson Electric Co., are spearheading a drive to keep the Cardinals in St. Louis. Ashcroft met with Bidwill Sunday and reportedly outlined the financial plans of a package that would include St. Louis businessmen buying $20 million of nonvoting stock in the team and a domed stadium being built downtown to house the football and baseball Cardinals and hockey's Blues.

Yesterday, officials announced plans to form a city-county sports authority that could issue revenue bonds to fund the domed stadium.

There is little doubt, sources said, that Bidwill would like the team to remain in St. Louis if possible, but attendance fell this season and he previously rejected a proposal including a 70,000-seat open-air stadium as economically unfeasible. Sources in St. Louis say, given time, the current plan may work, but it contains too many "unclear points" to be solved by the Jan. 15 NFL deadline for seeking league permission to move.

His current lease, which has seven years remaining, gives him an escape clause if the NFL approves the move. Otherwise, he would face a breach-of-contract suit if he moved without NFL approval, as Al Davis and Bob Irsay did previously.

The Missouri legislature, which could authorize such a sports authority, will not reconvene until Jan. 6, and it is likely a voter referendum would be necessary, meaning the certainty of financing would not be known by Jan. 15.

As far as selling stock in the team is concerned, Belgrad observed: "He's not interested in selling any part of the team. He has five children and he wants to pass it on to them. He bought out his own brother, so why is he going to welcome in a bunch of strangers?"

Belgrad said he has not heard from Bidwill or his financial people in two weeks. Belgrad sees that as a positive sign, even though those same representatives were in Phoenix as recently as Tuesday. "He's getting clarifications," Belgrad said. "The reason I didn't get a respose is that our proposal was self-explanatory. There's no need to talk until you begin negotiations."