Marsalis played college football at Tennessee A&I before playing professionally from 1969 through 1977. He was dominant enough as a cornerback to have only one touchdown thrown against him in four seasons.

In 1968, Marsalis was named an All-American by both The Sporting News and Times Magazine. He vaulted into the conscience of professional scouts at the 1968 Blue-Gray All-Star Classic by intercepting a record three passes in the game.^[1]

Marsalis was selected in the first round of the 1969 NFL Draft by the AFL's Kansas City Chiefs. An immediate starter at cornerback, Marsalis helped the Chiefs defeat the defending league champion New York Jets in the first game of the 1969 AFL playoffs, with two interceptions off the Jets' Joe Namath. After the Chiefs won the final AFL Championship Game a week later in Oakland 16-6, he started in the Fourth AFL-NFL World Championship Game for the Chiefs, defeating the Minnesota Vikings in the last World Championship game played between the AFL and NFL champions.

A two-time Pro Bowler with the Chiefs (1970 and 1971), Marsalis was selected by Pro Football Weekly as the 1969 AFL Defensive Rookie of the Year.^[2] A physical player, Marsalis' style of play as a defensive back was often associated with the physical "bump and run" tactics that would eventually be outlawed by the NFL.

After playing for the Chiefs through the 1976 season, Marsalis would play his last two professional seasons with the New Orleans Saints, retiring after the 1978 season. For his efforts at the college and professional level, Marsalis was selected to the Tennessee Sports Hall of Fame in 2012.^[3]

Marsalis would later work in banking as a loan officer. He briefly served as an assistant coach at Middle Georgia.