Tennell attended West Covina High School where he practiced football, basketball and track.
In basketball, he averaged 19 points and 12.5 rebounds, while helping this team reach the Sierra League championship.
Tennell accepted a football scholarship from UCLA and began his college career as a fullback.
[4] He was later re-signed after the season opener and played in the NFC title game against the Washington Redskins.
[5] On September 28, 1992, he was signed as a free agent by the Minnesota Vikings, after starter Mike Tice suffered an injury.
On December 29, 1992, he was signed as a free agent to replace blocking tight end Alfredo Roberts, who had suffered a season-ending right knee injury in the last game against the Chicago Bears.