He played college football at Tulane before transferring to Samford and was signed by the Ravens as an undrafted free agent in 2016, where he spent the next four seasons.
On September 10, in the 2017 season opener against the Cincinnati Bengals, Pierce recovered a Terrell Suggs-forced fumble, which came off of quarterback Andy Dalton, in the 20–0 victory.
[8][9] On July 28, Pierce announced he would opt out of the 2020 season due to the COVID-19 pandemic, and was placed on the reserve/opt-out list by the Vikings.
[14] He suffered a torn biceps in Week 3 and was placed on season-ending injured reserve on September 29.
[16] In 2024, Pierce recorded his first career interception late in the fourth quarter during Baltimore's season finale against the Cleveland Browns.