Hartsville unleashed its big red and black threshing machine and put it a nearly identical effort against Camden as it did a year ago.Last season in Kelleytown, the Red Foxes used a 247-yard, four touchdown night from Brian Rivers to upend the visiting Bulldogs, 41-7. In Friday’s home opener for Camden at Zemp Stadium, Rivers and wingback partner and fellow junior Shy McPhail combined for 271 yards and four touchdowns as the third-ranked guests left town with a 48-9 victory.Rivers, who missed last week’s win over Lamar with a shoulder injury, scored on runs of 46 and 51 yards on his first two carries of the night in helping the guests spring to 13-0 lead in the game’s first eight minutes. McPhail did his damage after intermission as he went for an 80-yard scoring scamper on the first play from scrimmage in the second half before going in from 10 yards on his final carry.