Mickens played college football at Washington, where he appeared in the majority of his career by changing his jersey number from 4 to 1 during his junior and senior years before he qualified for the 2016 NFL draft.[1] He had good, but unspectacular numbers, leading the team in receptions and receiving yards his junior and senior seasons but never cracking the Top 10 in the conference; he was the Huskies kick returner his freshman year, but only returned four punts over his college career, recording no touchdowns in either role.[2]
Mickens signed with the Oakland Raiders as an undrafted free agent on May 12, 2016.[5] He was waived by the Raiders on September 3, 2016, and was signed to the practice squad the next day.[6][7] After spending the entire 2016 season on the practice squad, he signed a reserve/future contract with the Raiders on January 9, 2017.[8] He was waived by the team on September 2, 2017.[9]
Jacksonville Jaguars (first stint)
On September 19, 2017, Mickens signed with the Jacksonville Jaguars' practice squad.[10] He was promoted to the active roster on October 21, 2017.[11] In Week 9, against the Cincinnati Bengals, he recorded a 63-yard punt return touchdown in the fourth quarter in a 23–7 win, earning him American Football Conference (AFC) Special Teams Player of the Week.[12] In Week 14, Mickens had a 72-yard punt return, but was stopped on the one-yard line, which set up a touchdown to give the Jaguars a 14-point lead over the Seattle Seahawks, again winning AFC Special Teams Player of the Week honors.[13] As a receiver, he recorded one reception prior to Week 15, but had four for 61 yards and two second-quarter touchdowns in a playoff-clinching 45–7 win over the Houston Texans.[14]
On October 15, 2018, Mickens was placed on injured reserve after suffering a fractured ankle in Week 6.[15]
Carolina Panthers
On July 24, 2019, Mickens was signed by the Carolina Panthers.[16] He was waived during final roster cuts on August 30, 2019.[17]
Tampa Bay Buccaneers
On December 19, 2019, Mickens was signed to the Tampa Bay Buccaneers practice squad. He was promoted to the active roster on December 24, 2019.[18] He was waived on July 31, 2020,[19] but re-signed on August 9.[20] He was placed on the reserve/COVID-19 list by the team on November 14, 2020,[21] and activated on November 30.[22] He was waived on December 7, 2020,[23] and re-signed to the practice squad two days later.[24] On December 30, 2020, Mickens was signed to the active roster.[25] Mickens was the Buccaneers' kickoff returner for Super Bowl LV, a 31–9 victory over the Kansas City Chiefs.[26]
On August 31, 2021, Mickens was released by the Buccaneers and re-signed to the practice squad.[27][28] He was signed to the active roster on September 10, 2021.[29] He was waived on October 18 and re-signed to the practice squad.[30][31]
Jacksonville Jaguars (second stint)
On November 24, 2021, Mickens was signed by the Jaguars off the Buccaneers practice squad.[32] In the 2021 season, Mickens mainly contributed on special teams for the Buccaneers and Jaguars in 11 total games.[33]
New York Giants
On December 14, 2022, Mickens was signed to the New York Giants practice squad. He signed a reserve/future contract on January 22, 2023.[34] He was released on August 27, 2023.[35]
Indianapolis Colts
On December 19, 2023, Mickens was signed to the Indianapolis Colts practice squad.[36] He was not signed to a reserve/future contract after the season and thus became a free agent upon the expiration of his practice squad contract.[37]