After spending 1970 as the third base coach of the Montreal Expos, working under Gene Mauch, Williams returned to the managerial ranks the next year as boss of the Oakland Athletics, owned by Charlie Finley. The iconoclastic Finley had signed some of the finest talent in baseball – including Catfish Hunter, Reggie Jackson, Sal Bando, Bert Campaneris, Rollie Fingers and Joe Rudi – but his players hated him for his penny-pinching and constant meddling in the team's affairs. During his first decade as the Athletics' owner, 1961–1970, Finley had changed managers a total of ten times.