Donald J. Trump is expected to appear in a Manhattan courtroom on Monday to seek another delay of his criminal trial on charges that he covered up a sex scandal that could have derailed his stunning victory in the 2016 presidential election.

The hearing to finalize a trial date, in what would be the first criminal prosecution of a former American president, will come as Mr. Trump is racing to stave off a financial crisis arising from a judgment in another case: a $454 million judgment in a civil fraud suit brought by New York’s attorney general.

The flurry of activity will unfold nearly a year to the day after the Manhattan district attorney’s office filed an indictment of Mr. Trump, accusing him of falsifying business records related to a hush-money deal with a porn star, Stormy Daniels.

The trial was to have begun Monday, but the New York State Court judge overseeing it, Juan M. Merchan, delayed it until at least April 15, citing newly disclosed documents. They came from federal prosecutors who had previously investigated Michael D. Cohen, the former president’s longtime fixer, who arranged the hush-money deal and is expected to be a star witness against Mr. Trump.

Mr. Trump, casting the disclosure as evidence of prosecutorial misconduct, has asked Justice Merchan to delay the trial 90 days, or throw out the case altogether.

The move underscores Mr. Trump’s long-running effort to stall all his legal entanglements until after the November election, when he hopes to win back the presidency, which would effectively halt the criminal cases against him. And with Mr. Trump’s three other criminal trials mired in delays, the Manhattan case might be the only one to move forward before voters head to the polls.