The biggest catch in the Mavericks' summer free-agency expedition is point guard Jose Calderon. That isn't by design, of course. When free agency opened, the Mavs hoped to talk Dwight Howard into coming to Dallas. Howard, however, headed to Houston. The Mavs then opted not to offer Andrew Bynum a contract before he committed to the Cavaliers, scared away by his bad knees. Their starting center is to be determined, with stopgap candidate Samuel Dalembert meeting Thursday with the Mavs.