 He made his NFL debut on October 1, 1922, helping the Independents to a 19-14 victory over the Green Bay Packers by swatting down a pass from Packers quarterback Curly Lambeau on Green Bay’s final drive of the game.After Rock Island completed their 1922 season schedule, Slater joined Fritz Pollard and Paul Robeson on the Milwaukee Badgers for two games at the end of the 1922 season.In 1923, he returned to Rock Island and played his next four seasons – five in all – with the Independents.