From Marc Spears: (http://www.boston.com/sports/basketball/celtics/extras/celtics_blog/2009/07/cs_offer_sheed.html)An NBA source said that the Celtics offered Detroit 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 ...