The Larry O’Brien trophy was in the building, as was Boston Celtics legend Bill Russell, along with boxes and boxes of T-shirts and hats designating the Celtics as the 2010 NBA champions. None of them became part of the postgame program. The Lakers made sure of it, clearly and convincingly, thumping the Celtics, 89-67, and forcing a Game 7, in case it wasn’t clear by the time Russell headed for the exit with three minutes left Tuesday at Staples Center.