Professional career

NFL

Davidson was selected in the fourth round of the 1961 NFL draft by the New York Giants, but was traded in training camp to the Green Bay Packers.^[6]

As a rookie, he played mostly special teams for the Packers in 1961, who beat the Giants 37–0 in the championship game, the first of five NFL titles for head coach Vince Lombardi.^[7] During training camp in 1962, Davidson was traded to the Washington Redskins for a fifth round draft choice.^[8] He played there in 1962 and 1963, until he was waived in September 1964 final cuts after not meeting the team's strict weight guidelines.^[6][9]

AFL

Davidson is best remembered for his play with the American Football League Oakland Raiders. Al Davis signed him as a free agent shortly after his release from the Redskins and he thrived as a pass rusher under head coaches Davis, John Rauch, and John Madden. Davidson played in Oakland from 1964 through 1972, and was part of the league merger in 1970. He was an AFL All-Star in 1966, 1967, and 1968.

The Raiders won the AFL championship in 1967 and played in Super Bowl II, but were overmatched by the Green Bay Packers. Oakland advanced to the AFL title games the next two seasons but lost to the New York Jets in 1968 and the Kansas City Chiefs in 1969, the league's last game. A stretched Achilles tendon in 1972 kept him on the sidelines that entire season.^[10]

NFL merger and Dawson–Taylor incident

On November 1, 1970, after the AFL-NFL merger, the defending champion Kansas City Chiefs led the Raiders 17–14 late in the fourth quarter. A long run for a first-down by Chiefs quarterback Len Dawson apparently sealed victory for the Chiefs in the final minute when Dawson, as he lay on the ground, was speared by Davidson, who dove into Dawson with his helmet at full running speed, provoking Chiefs' receiver Otis Taylor to attack Davidson. After a bench-clearing brawl, offsetting penalties were called, nullifying the first down under the rules in effect at that time. The Chiefs were obliged to punt, and the Raiders tied the game on a George Blanda field goal with eight seconds to play. Davidson's play not only cost the Chiefs a win, but Oakland won the AFC West with a season record of 8–4–2, while Kansas City finished 7–5–2 and out of the playoffs.^[11][12] After the season, the NFL changed its rules regarding personal fouls, separating those called during a play from those called after it. In 1976, the NFL further modified its rules, explicitly calling out a late hit such as Davidson's as illegal.^[13]

Davidson's hit on Dawson was not an isolated occurrence; Winston Hill, a Jets player of the era, called Davidson "the No. 1 cheap-shot artist" in the league. A journalist for The New York Times wrote that Davidson "probably was responsible for more late hits than any other player" of his time, and was known for going after the opposing team's quarterback. Davidson cultivated a persona as a "villain" and embraced this reputation, even wearing a handlebar mustache.^[14]

WFL

Three years out of football, Davidson signed with the Portland Storm in early September 1974, already midway through the World Football League's inaugural 1974 season.^[15][16] While with the Storm, he lived in his motor home that he drove up from California.^[5] A late season knee injury in early November ended his season and playing career.^[17]

Entertainment career