Fanning was selected in the first round (9th selection) of the
1975 NFL draft by the Los Angeles Rams. He was touted to be the successor to
Merlin Olsen, who was entering his 14th season in 1975. As a rookie, Fanning broke his leg, and saw limited action after returning midseason. In 1976, in spot duty for Olsen, he recorded four
sacks. Fanning took over as the starter at left tackle in 1979 after an injury to
Cody Jones. Fanning had eight sacks in 1979 and ten sacks in 1980. He led the Rams in sacks in the strike-shortened 1982 season with five. Prior to the 1983 season, Fanning was traded to the
Detroit Lions. He played one season with the Lions and was signed as a free agent by the
Seattle Seahawks in 1984. He had seven sacks in 1984 as a pass-rush specialist for the Seahawks. ==Later life==