Baltimore's Board of Estimates yesterday approved a one-year extension of the Orioles' lease on Memorial Stadium under which any profits are split between the Orioles and the city but losses are absorbed by the team.

City Comptroller Hyman Pressman said there was no opposition to the extension despite the fact that the Orioles lost money last year and there were no profits to share. He said the Board of Estimates, whose action is final, approved the extension following a recommendation last week of the city's Board of Parks and Recreation.

Currently pending in Annapolis is legislation that would authorize a $7.5 million bond issue for improvements at Memorial Stadium, and city officials have indicated they will ask the Orioles to sign a longer term, possibly of six years, lease if the legislation passes.

However, Orioles owner Edward Bennett Williams said he had no idea what, if any, legislation would be forthcoming, and he said the Orioles would first have to examine the details of any long-term proposal.

"All we did was roll over last year's lease," he said.

Pressman said he plans to have an auditor examine the Orioles' books to make sure the team did, in fact, lose money. Skeptics have suggested the new lease arrangement could become a way for the city to pay for increased spending by the Orioles. But Pressman said he has no reason to believe there was anything amiss.

"I think Mr. Williams is an honorable person and wouldn't knowingly put one over on us," he said.

The Orioles are reported to have lost between $500,000 and $1 million last year but are known to contend that if the team had made the playoffs and had it not been for two major rainouts, there would have been a profit.

Despite the fact that there were no profits to share, Baltimore receives a flat 10 percent admissions tax on each ticket sold. For last season that would amount to about $800,000 for the city treasury.