Boston sent the whole cavalry to Wallace’s place, and asked him to sign on the dotted line: “An NBA source said that the Celtics offered Pistons free agent F/C Rasheed Wallace a contract using the mid-level exception today during a three-hour meeting in Detroit. The Celtics All-Star trio of Kevin Garnett, Paul Pierce, and Ray Allen, coach Doc Rivers, president Danny Ainge, and managing partner Wyc Grousbeck all attended the meeting. While interested, the source said Wallace was in...