He was the head coach of the New Orleans Saints of the National Football League (NFL) from the middle of the 1970 season until his dismissal after four preseason games in 1973.
[12] Roberts was hired by Saints owner John Mecom on November 3, 1970, replacing Tom Fears after New Orleans began 1970 with a 1–5–1 record.
The Saints won 19–17 when Tom Dempsey kicked a 63-yard (58 m) field goal, a record which broke the previous NFL mark by seven yards.
With the second pick in the 1971 NFL draft, Roberts and Mecom selected Ole Miss quarterback Archie Manning, who became the cornerstone for the woebegone franchise for the next decade.
Four weeks later, the Saints stunned the eventual Super Bowl champion Dallas Cowboys 24–14, but New Orleans finished the season 4–8–2.
New Orleans regressed sharply in 1972, falling back to 2–11–1, and Roberts was fired shortly after a 31–6 preseason loss to the New England Patriots on August 25, 1973.