Parachuting in to plead his case for the Sacramento Kings, Mayor Kevin Johnson arrived Friday at the site of the NBA All-Star Game to lobby to keep the team from relocating to Seattle. He didn't bring a lineup of investors to buy the Kings, or a completed financial package to build the new arena needed to secure the team's future in Sacramento. But Johnson spent hours in a series of closed-door meetings with key NBA officials, hoping his visit to Houston would help lay the groundwork to block the Maloof family's proposed sale of the Kings to a group that would move them to Seattle next season. The mayor wasn't available for comment late Friday. A source close to the situation characterized the talks as "positive and productive." The source wouldn't identify the people who met with Johnson. The source, who declined to be identified, said the NBA officials seemed to appreciate that Sacramento has "an approved arena plan" - the financing package negotiated a year ago, blessed by the NBA and later approved by the City Council before it was renounced by the Maloofs. Although the proposed site might shift from the railyard to Downtown Plaza, this source said league officials understand that the basic building block is still in place - the city's willingness to pump in a $255 million subsidy. "The biggest piece of the puzzle is the public financing," the source said. Seattle has its own financing plan, tentatively approved by city and county officials last fall, including $200 million in public funding.