The D.C. lottery board reluctantly agreed yesterday to a day's delay of its planned signing of a contract to operate the city's first daily numbers game so that a judge could decide whether to postpone the signing even further.

The board had hoped to sign a contract with Lottery Technology Enterprises, the joint venture comprising a Rhode Island-based computer firm and four black-owned Washington firms that were selected by the board last month over two competing companies.

But just hours before the expected signing, lawyers for D.C. Data Company, one of the losing bidders, marched into D.C. Superior Court and asked for a temporary restraining order to block the event.

After nearly three hours of arguments, Judge Eugene N. Hamilton won--under threat of a formal court order--a promise from city lawyers that the contract would not be signed last night. Meanwhile, Hamilton scheduled a hearing this morning to help him determine whether D.C. Data has sufficient grounds for him to grant the 10-day temporary retraining order prohibiting the signing.

D.C. Data's lawyers asked that lottery board Chairman Brant Coopersmith and the agency's executive director, Chester C. Carter, be available to testify today about how Lottery Technology was selected. The city's lawyers said they would appear.

D.C. Data is claiming that the Rhode Island computer company involved in Lottery Technology, Gaming Systems Corp., is not financially capable of running the District's lottery and that it is not a true minority-run enterprise, one of the prime considerations in the lottery board's decision.

Hamilton had tried to get the city to voluntarily agree to a 10-day delay in the contract signing so that a contract review committee could assess whether the lottery board followed its various regulations in picking Lottery Technology.

But Assistant Corporation Counsel Joseph P. Hart checked with other city lawyers and the board and then told Hamilton they would not consent to a voluntary 10-day delay.