He played college football at Boise State and was signed by the Arizona Cardinals as an undrafted free agent in 2019.

A. J. Richardson was born June 2, 1995, in Lomita, California and played football at Narbonne High School.

During his high school career, as a senior, Richardson totaled 60 receptions for 1,000 yards and 18 touchdowns and rushed 22 times for 121 yards and four touchdown and was named a Semper Fidelis All-American, named to All-Marine League, all-city section and All-State teams.

[3] On August 31, Richardson was waived during final roster cuts and was later re-signed to the practice squad, but released a day later.

[8] On October 22, 2022, Richardson signed with the Michigan Panthers of the United States Football League (USFL).