Getty Former Los Angeles Lakers center Colin Castleton. The Philadelphia 76ers are in the midst of a nightmare season and they are far out of the playoff race. The best they can hope for is to see some young players step up and see what they can do. This has led them to add a young big man to the roster. According to NBA insider Jake Fischer , the 76ers have given a 10-day contract to free agent center Colin Castleton. Castleton first came into the NBA as an undrafted free agent signing of the