Bill Fitch, five days since he resigned as Boston Celtics coach and said he had "no immediate plans," signed a multiyear contract yesterday to coach the Houston Rockets. His first-year goal, Fitch said, will be to give the Rockets the best attitude in the NBA.

Terms of the contract were not announced, but the Rockets' package was believed similar to the four-year, $200,000-per-year offer made last week to Tom Heinsohn, another ex-Celtics coach. Rockets owner Charlie Thomas said the contract was for "more than one year and less than 20." It's "multiday," quipped Fitch.

Fitch left Boston with three years left on a contract worth an estimated $200,000 per year.

He led the Celtics to a 242-86 record and one league championship in four years and now undertakes to rebuild the Rockets, coming off an NBA-worst 14-68 season. Fitch did not promise immediate success although the Rockets have the No. 1 pick in the June 28 draft and will use it to select Virginia's Ralph Sampson.

"I don't think it's possible in one year, even if you get the greatest talent together, to win the championship," Fitch said. "It takes time to develop the chemistry . . . and that will be our goal."

The San Antonio Spurs' attempt to block Coach Stan Albeck from signing with any other NBA team has been moved from state to federal court.

Spurs' owner Angelo Drossos obtained a temporary restraining order May 26 and kept the New Jersey Nets from negotiating with the coach. Now the Nets have filed a petition for removal, putting the case in federal court--while Albeck filed to dissolve the restraining order.

Albeck's motion said, "On the night of the Spurs' last game of the season--a heartbreaking last-second loss to the Los Angeles Lakers (NBA Western finals, Game 6)--Drossos came down to the locker room . . . and blamed Albeck . . . Albeck was deeply hurt and furious at this."

Drossos denied blaming or, in the coach's word, "browbeating" Albeck.