Kelly attended Bethel High School in Hampton, Virginia, where he played football and baseball, and ran track. He played defensive end and tight end for the football team, registering six sacks and five interceptions on defense, and catching 18 passes and scoring five touchdowns on offense during his senior year to win All-State honors. He was timed at 4.5 seconds in the 40-yard dash, which was unusually fast for a defensive lineman. As a member of the track team, Kelly won the state's high hurdles title as a sophomore, with a best of 14.1 seconds. He received All-State honors in baseball, and was drafted by the Detroit Tigers in the 1989 June Amateur Draft.
College career
Kelly initially committed to South Carolina in 1989, but switched his commitment to Tennessee following the death of South Carolina coach Joe Morrison. Due to a lack of depth on the defensive line, he played in eight games during his freshman year as a backup to veteran Marion Hobby, picking up 6 tackles and a sack. While working with defensive coaches Larry Lacewell and Rex Norris, Kelly remained on the second unit during the 1990 season, picking up 21 tackles and a team-leading 5 sacks. He had two sacks in Tennessee's 45-3 win over Florida, and forced a fumble that led to a score in the Vols' 26-26 tie against Auburn. During his junior year in 1991, Kelly registered 23 tackles and 5.5 sacks, playing mostly as a backup to senior Chuck Smith. He had three tackles and a sack in the Vols' 30-21 win over Auburn, and registered four tackles and a sack in the team's loss to Florida. He had a sack and forced a fumble in Tennessee's 25-24 loss to Alabama. He tallied four tackles and a sack in Tennessee's loss to Penn State in the 1992 Fiesta Bowl. Kelly's first career start came in Tennessee's 1992 season-opening win over Southwest Louisiana, in which he registered three tackles and a sack. He registered 2.5 sacks in Tennessee's 34-31 win over Georgia, and led a rushing defense that held Florida to just 68 yards on the ground in the Vols' 31-14 win over the Gators. He recovered a fumble in the fourth quarter of Tennessee's 17-10 loss to Alabama, and registered a sack in Tennessee's 38-23 win over Boston College in the 1993 Hall of Fame Bowl. He finished the season with 38 tackles, a team-leading 11 sacks, and a team-leading 10 tackles-for-loss. He was named All-SEC and second-team All-American at the end of the season. During his four years at Tennessee, Kelly registered 88 tackles, 22.5 sacks, 14 tackles-for-loss, and two forced fumbles. He is fourth on the school's career sacks list, trailing only Reggie White, Leonard Little and Jonathan Brown. His 11 sacks in 1992 is tied with Little's 1995 tally for the school's fourth-highest single-season total. In October 2014, Kelly was named Tennessee's selection for that year's SEC Football Legends Class.
Professional career
Kelly was selected by the San Francisco 49ers in the first round of the 1993 NFL Draft. During his rookie year, he played in 14 games and started in five, registering one sack. During the 1994 season, Kelly played in 11 games, and registered 9 tackles and 3.5 sacks. He appeared with the 49ers in the team's 49-26 victory over San Diego in Super Bowl XXIX. Kelly was cut by the 49ers prior to the 1995 season. Coach George Seifert stated Kelly hadn't developed the way the team had hoped. He was claimed on waivers a few days later by the Cincinnati Bengals. He appeared in all 16 games for the Bengals in 1995, playing primarily as a speed rusher on passing downs. He was cut by the Bengals prior to the 1996 season, but was re-signed for two games in October. He finished the season with the Atlanta Falcons. During his four seasons in the NFL, Kelly registered 27 tackles, 5.5 sacks, two forced fumbles, a fumble recovery, and a pass broken-up.
Kelly returned to Knoxville, Tennessee, with his family, following his NFL career. He works as a sales representative for Covidien, and served as a youth football coach from 2003 to 2009. Kelly met his wife, Renee, a former Vol Hostess, on a recruiting trip to Tennessee in 1989. Their son, Todd Kelly, Jr., was a consensus four-star defensive back at the Webb School of Knoxville, and played for Tennessee from 2014 to 2018. Their daughter Clarke was a cheerleader at Alabama and graduated in 2015.
