On December 19, 2016, Northrup was signed to the Los Angeles Rams's practice squad.[4] On January 3, 2017, he was signed to a futures deal.[5] He was waived on June 20, 2017.[6]
Montreal Alouettes
On September 20, 2017, Northrup was signed with the Montreal Alouettes of the Canadian Football League (CFL).[7] In week 15, Northrup made his professional debut and compiled six defensive tackles.[8] He played again in week 18 and made two tackles.[9] In week 19, Northrup had 4 defensive tackles.[10] In his final game in the CFL, week 20, Northrup made 10 defensive tackles and 1 special teams tackle.[11]
Orlando Apollos
In 2019, Northrup joined the Orlando Apollos of the Alliance of American Football (AAF).[12] When the AAF suspended operations in week 8, he finished with 35 solo tackles, 27 assists, 62 total tackles, and 1 sack. He led the league with assists and tied for fifth in total tackles.[13]
Tampa Bay Vipers
In October 2019, Northrup was selected by the Tampa Bay Vipers in the 2020 XFL draft.[14] Northrup ended up starting 1 of 5 games, and finished with 12 solo tackles, 3 assists, 15 total tackles, and 1 sack.[15] He had his contract terminated when the league suspended operations on April 10, 2020.[16]
Houston Gamblers
Northrup was selected in the 21st round of the 2022 USFL draft by the Houston Gamblers.[17] He became a free agent when his contract expired on December 31, 2022.
In December 2020, Northrup made his amateur MMA debut, in which he defeated Mike Anderson by submission in the first round. In March 2021, he fought Josh Mercado in which he won via submission in the third round. In July 2021 he fought Kevin Church, in which he won by knockout. In December 2021, he defeated Darius Kennedy in bare knuckle by knockout in the first round. Northrup's final match was in January 2022, where defeated Jay Mitchell in 35 seconds by knockout.[20]
On January 26th, 2024 Northrup competed on the main card of Karate Combat: Kickback 1 in Miami Florida. He would go on to lose via split decision.
