Mimoun did not compete in 1957 but returned in 1958 with a runner-up finish behind Stan Eldon in the individual race at the International Cross Country Championships and his first national marathon title.[38] He placed seventh in the 10,000-meter event at the 1958 European Athletics Championships. In 1959 he came sixth in the individual race at the International Cross Country Championships,[38] and won national titles in the marathon and cross country.