Ollison was drafted by the Atlanta Falcons in the fifth round (152nd overall) of the 2019 NFL draft.[6] In the Week 11 matchup against the Carolina Panthers, Ollison scored from two yards out on his first career rushing attempt during the second quarter of the 29–3 win.[7] During Week 12 against the Tampa Bay Buccaneers, Ollison scored his second career touchdown.[8] As a rookie, he appeared in eight games and recorded 22 carries for 50 rushing yards and four rushing touchdowns.[9]
On September 2, 2021, Ollison was waived by the Falcons and re-signed to the practice squad.[10][11] He was promoted to the active roster on December 11.[12] During the Week 18 matchup against the New Orleans Saints, he scored his fifth career touchdown on a 19-yard rushing attempt in the 30–20 loss.[13]
On March 28, 2022, Ollison re-signed with the Falcons.[14] He was waived on August 30.[15]
Dallas Cowboys
On September 1, 2022, Ollison was signed to the Dallas Cowboys practice squad.[16] The signing reunited him with defensive coordinatorDan Quinn, who was his head coach with the Falcons. On October 29, 2022, he was elevated to the active roster from the practice squad. On November 12, 2022, he was elevated to the active roster from the practice squad. On December 29, 2022, he was elevated to the active roster from the practice squad. His practice squad contract with the team expired after the season on January 22, 2023.
Jacksonville Jaguars
On February 13, 2023, Ollison signed a reserve/future contract with the Jacksonville Jaguars.[17] He was released on August 29, 2023, as a part of the team’s final roster cuts.[18]
Pittsburgh Steelers
On September 2, 2023, Ollison was signed to the practice squad of the Pittsburgh Steelers.[19] He was released on December 11, 2023.[20]