Rankin, a 6-1, 228-pound linebacker from Wedgefield, Florida had more than 20 offers before picking the Bulldogs. He was an All-State player last fall.
Scout.com's Mike Bakas says that Rankin "plays with tremendous instincts and football IQ."
Rankin ended his junior season in 2011 with 189 tackles, seven sacks, eight caused fumbles and a touchdown.
An FFA member, Rankin is the Bulldogs' second commitment of the day.