By Mike McDermott Stopping the Patriots' offense is always a difficult challenge, and this week a former Rhode Island high school football star will be part of the team that tries to do it. Brad White, a 2000 graduate of Bishop Hendricken High School and former Portsmouth resident, is a first-year defensive assistant on the Colts staff. White (that's his 1999 All-State picture at right) was teammates at Hendricken with future NFL player Will Blackmon.