Ricky Williams, a one-time Toronto Argonaut running back who battled anxiety issues and became known as one of the most cerebral, if at times odd, professional football players of his era, retired from the NFL on Tuesday. Williams played for the Argos for one season in 2006 after failing three drug tests in the U.S. In a 2006 interview with Maclean’s, Williams said he didn’t regret his pot-smoking ways. “If I’d never smoked marijuana,” he said, “chances are I would have never found yoga.” While in Toronto, he struck up a deep, if unexpected friendship with his neighbour, a 42-year-old midwife raising four children. (The Toronto Star’s Jennifer Yang wrote about their relationship in 2010.) Considered one of the greatest college running backs of all time, Williams was a bit of a bust early in his NFL career. He struggled in the professional limelight and once took an entire year off to travel the world. He later returned to football and became a serviceable, if never quite spectacular pro. He finished last season as a backup for the Baltimore Ravens. At 34, he plans to travel and go back to school.