WASHINGTON — The Lakers have agreed to trade backup guard Sasha Vujacic and a first-round draft pick in 2011 to the New Jersey Nets for forward Joe Smith as part of a three-team deal. Terrence Williams will go from the Nets to the Houston Rockets. The trade cannot be formally announced until Wednesday, the first day players who signed free-agent contracts last summer can be traded.

Smith, 35, has played only five games this season for the struggling Nets. Vujacic, 26, was averaging 1.8 points in 11 games going into tonight’s contest against the Washington Wizards. His role has been reduced this season, his last in a three-season, $15-million contract. By trading him, the Lakers will save some luxury tax money. Smith is making “only” $1.35 million this season. The Lakers’ payroll is $95.7 million, highest in the NBA.

The news took Vujacic by surprise. He didn’t learn to it until told by a team official after the Lakers’ victory over the Washington Wizards tonight. Here’s some of what he had to say after the game: “I don’t know what to say at the moment. Right now, it’s just a rumor. … They (the Nets) are a young team, they’re rebuilding their franchise and it sounds interesting.”