They used to call them donut teams, those with a hole in the middle.These days, an NBA roster without a dominant big man would be more of a croissant team.You know, with that opening on the perimeter where the tips don't meet, a space reserved for anybody who is 6-10 or bigger, can make 3-pointers and double as a rebounding and/or defensive stud.That's who the Mavericks are looking for in free agency.