After going undrafted in the 2014 NFL draft, Pennel signed with the Green Bay Packers on May 12, 2014.[4] Pennel joined Jayrone Elliott as undrafted players to make the Packers roster. During his rookie season in 2014, Pennel made 13 game appearances with 8 tackles. In 2015, Pennel appeared in all 16 games, starting 5 of them with 24 tackles, one sack, and one forced fumble.[5]
On February 19, 2016, Pennel was suspended for the first four games of the 2016 season due to violating the league's substance abuse policy.[6] Pennel was then suspended for the final four games of the 2016 season for again violating the league's substance abuse policy.[7] In eight games of 2016, Pennel finished with seven tackles and a pass defended.[8]
On January 9, 2017, Pennel was released by the Packers.[9]
New York Jets
On February 6, 2017, Pennel was claimed off waivers by the New York Jets.[10] He re-signed with the Jets on March 16, 2017.[11] He played in all 16 games in 2017, recording a career-high 35 tackles.
On March 16, 2018, Pennel signed a three-year contract with the Jets.[12]
On February 19, 2019, the Jets declined the option on Pennel's contract, making him a free agent at the start of the new league year.[13]
New England Patriots
On March 14, 2019, Pennel signed a two-year contract with the New England Patriots.[14] On August 26, 2019, Pennel was released by the Patriots.[15]
On April 6, 2020, Pennel was re-signed to a one-year contract.[19] He was suspended for the first two games of the 2020 season on August 25, 2020.[20] He was reinstated from suspension and activated to the roster on September 23, 2020.[21]
Chicago Bears (first stint)
On June 18, 2021, Pennel signed a one-year deal with the Chicago Bears.[22] He was placed on injured reserve on August 24, 2021.[23] He was released on August 31.
Atlanta Falcons
On September 15, 2021, Pennel was signed to the
practice squad of the Atlanta Falcons.[24] On October 5, 2021, Pennel was promoted to the Falcons active roster.[25]
Chicago Bears (second stint)
Pennel signed with the Bears on June 13, 2022.[26] He was released on September 9, and re-signed to the practice squad. He was promoted to the active roster on September 12.[27] Pennel appeared in all 17 games for the Bears, where he recorded 26 total tackles and one forced fumble. He was ejected from the team's Week 6 contest against the Patriots for delivering a blind-sided block that concussed center David Andrews.[28]
Kansas City Chiefs (second stint)
On October 24, 2023, Pennel was signed to the Chiefs practice squad.[29] Pennel helped the Chiefs reach Super Bowl LVIII where they defeated the 49ers 25–22 to give Pennel his second Super Bowl ring.[30] Pennel had six tackles in the game and was instrumental in limiting the effectiveness of the 49ers' running game in the second half.[31]
On March 13, 2024, Pennel re-signed with the Chiefs.[32]
^Greenberg, Ethan (February 7, 2017). "Jets Claim DL Mike Pennel". NewYorkJets.com. Archived from the original on February 26, 2017. Retrieved February 7, 2017.
^Alper, Josh (March 16, 2017). "Jets sign Mike Pennel". ProFootballTalk.NBCSports.com. Retrieved March 20, 2021.
^Alper, Josh (March 16, 2018). "Jets re-sign Mike Pennel". ProFootballTalk.NBCSports.com. Retrieved March 20, 2021.