Attended Calvary Christian Academy, where he played wide receiver, defensive back and kick returner. He totaled 877 yds. and 15 TDs on 52 recepts. as a senior, with 1 rushing TD and 2 INTs and a TD on defense. Had 59 recepts. for 1,094 yds. and 12 TDs as a junior, with one KO return TD and 2 INTs. As a sophomore, finished with 42 recepts. for 906 yds. and 10 TDs with 1 INT and 1 punt return TD. In addition to football, also lettered in basketball and track.
College career
Appeared in 36 games over his five years at Iowa and totaled 144 tackles, 19 PDs, 3 INTs, 2.5 TFLs, 5.0 sacks, 2 FFs and 2 FRs. As a senior in 2016, started all 9 games and registered 37 tackles, 3 PDs, and 1 FF, earning Honorable Mention All-Big Ten honors. In 2015, appeared in 14 games, finishing with 54 tackles, 10 PDs, 1 FF and 2 INTs. As a sophomore, appeared in all 13 games and recorded 53 tackles, 6 PDs, 2.0 TFLs, 2 FRs and 1 INT. Did not see game action in 2013 after redshirting in 2012. Mabin transitioned from wide receiver to defensive back for Iowa's 2013 spring practice. He graduated from The University of Iowa with a degree in health and human physiology.
On June 1, 2017, Mabin signed with the Buffalo Bills. He was waived on September 12, 2017 and was signed to the practice squad the next day. He was promoted to the active roster on October 7, 2017. He was waived by the team on October 16, 2017.
On October 18, 2017, Mabin was signed to the San Francisco 49ers' practice squad. He was promoted to the active roster on November 1, 2017. On October 30, 2018, Mabin was waived by the 49ers and was re-signed to the practice squad. On November 8, 2018, Mabin was promoted to the 49ers active roster. On August 16, 2019, Mabin was waived by the 49ers with an injury designation. He was placed on injured reserve the next day. He was waived on August 26.
Cincinnati Bengals
On September 24, 2019, Mabin was signed to the Cincinnati Bengals practice squad, and was promoted to the active roster the next day. He was waived on October 7, 2019 and re-signed to the practice squad. He was promoted back to the active roster on October 30. Mabin re-signed with the Bengals on March 31, 2020.
