Cox attended Western Illinois University and was a mass communications major and a letterman in football.

In his sophomore campaign, Cox blossomed and helped lead the Dolphins to an 11–5 record and the AFC Championship Game.

Cox earned his second Pro Bowl selection in 1994, starting 16 games at middle linebacker, leading the team with 100 tackles.

[3] Miami finished the season 10–6, winning the Wild Card Game against the Kansas City Chiefs, 27–17 before losing the Divisional Playoff to the San Diego Chargers, 22–21.

He again started every game at middle linebacker, finishing the year with a team high 119 tackles, 7.5 sacks and three forced fumbles.

While with Miami, Cox made his distaste towards division rival Buffalo widely known, giving the finger towards fans in 1993 and getting into a fist-fight with Bills fullback Carwell Gardner in 1995.

On his way back to the locker room, Cox repeatedly spit into the air, intended as gesture to the heckling Buffalo fans.

[4] Cox would go on to play seven more seasons in the NFL for the Chicago Bears, New York Jets, New England Patriots, and New Orleans Saints.

In a career encompassing 165 games, Cox recorded 764 tackles, tallied 51.5 quarterback sacks, caught four interceptions and forced 22 fumbles.

Throughout his NFL career, Cox was easily recognizable on the field due to the unusual headrest- or "surfboard"-style neck roll he wore and colored to match his uniform jersey.