 Walsh formulated what has become popularly known as the West Coast offense during his tenure as assistant coach for the Cincinnati Bengals from 1968 to 1975, while working under the tutelage of Brown (and before embarking on his legendary coaching tenure with the San Francisco 49ers in the 1980s).Bengals quarterback Virgil Carter was the first player to successfully implement Walsh's system, leading the NFL in pass completion percentage in 1971.Ken Anderson replaced Carter as Cincinnati's starting quarterback in 1972 and was even more successful.