He played college football for the Western Michigan Broncos, where he became the NCAA Division I FBS leader in career receiving yards.

As a sophomore, he was called up to varsity to play alongside his big brother Titus Davis, who went on to become the all-time leading receiver in touchdowns and yards from scrimmage for Central Michigan University.

During his youth football years playing for the Wheaton Rams he forged a close friendship with the son of former Tampa Bay Buccaneers player Dan Graham.

The Grahams hired a personal tutor for him so he could get his grade point average high enough to be eligible to receive an NCAA scholarship.

[7][8] Against the Toledo Rockets on November 25, 2016, Davis became the all-time FBS leader in receiving yards, breaking the record previously held by Nevada's Trevor Insley.

†NCAA Division 1 FBS all-time record Davis attended the NFL Scouting Combine, but was unable to participate in athletic drills due to an ankle injury.

[12] Despite an injury leaving Davis unable to perform pre-draft workouts, he was still considered a top wide receiver prospect eligible for the 2017 NFL draft class.

[20] On January 13, 2018, Davis caught his first two NFL touchdowns from Marcus Mariota in the 2017 American Football Conference Divisional Round 35–14 loss to the New England Patriots.

[21] During Week 4 against the Philadelphia Eagles, Davis had a career game with nine receptions for 161 yards, including the game-winning touchdown from Marcus Mariota in overtime.

[30] In the Divisional Round of the playoffs against the Baltimore Ravens, he caught a three-yard touchdown pass from running back Derrick Henry in the 28–12 road victory.

[33] In the 2020 regular season opener for the Titans, Davis had seven receptions for 101 receiving yards in the 16–14 victory over the Denver Broncos on Monday Night Football.

[37] During Week 10 against the Indianapolis Colts, Davis elected to play a day after the death of his older brother to cancer, recording five catches for 67 yards.

[40] In Week 13 against the Cleveland Browns, Davis caught eleven passes for 182 yards, both career highs, along with a touchdown reception in the 41–35 loss.