Contract negotiations between the NBA and its referees union became so ugly this week that the NBA threatened to fire all referees who refused to work the playoffs.

The National Association of Basketball Referees is represented by Los Angeles attorney Fred Slaughter, who said the referees unanimously empowered him on Monday to initiate, ata his discretion, a work stoppage.

The action was avoided late yesterday, when the NBA and the referees agreed to continue negotiating a new contract. The current contract, which expires in December, is said to have a no-strike provision.

* 76ERS: Charles Barkley could be traded if the club gets the right offer, owner Harold Katz said.

"I think it's obvious that we have to come back with a different-type team," Katz said.