That Puerto Rican court went ahead and imposed sentence on Bobby Knight in absentia yesterday -- with the judge increasing the Indiana University basketball coach's pending jail term from six months to a possible nine months.

"If Knight steps foot in Puerto Rico," said the U.S. assistant district attorney in San Juan, "he will be arrested and jailed."

And jailed, decreed Judge Rurico Rivera, an extra day (up to 90) for each $5 of Knight's $500 fine (imposed Aug. 23 along with the six months) left unpaid.

The prosecutor said Knight had broken a promise to appear in court, and the case now moves to the Justice Department's extradition division, where he estimated "within a month" it will be decided whether to ask Gov. Carlos Romero Barcelo to formally request extradition from Indiana.

"Romero has said he would not ask, and Indiana Gov. Otis R. Bowen has said he would refuse to deliver the coach to the island where his U.S. team's drive to the basketball gold medal in the Pan American Games was marred by a July 8 hassle with a policeman who brought charges of aggravated assualt.

And Knight would have to be dragged back to Puerto Rico, he declared a few hours before sentencing -- issuing a 20-page account of the entire Pan Am basketball episode to the media and appearing at a Bloomington, Ind., news conference with corroborating witnesses to his innocence including five players on the U.S. squad.