Walker then was a minor league manager for six seasons. He helmed the unaffiliated Houston Buffs of the American Association for part of 1959, then managed at Double-A in the Dodgers' and Yankees' farm systems from 1960 through 1964. After  he was a pitching coach for the Washington Senators, New York Mets and Atlanta Braves, working closely with managers Gil Hodges, Yogi Berra and Joe Torre, among others.
Walker was a minor league manager for six seasons. He led the unaffiliated Houston Buffs of the American Association for part of 1959, then managed at Double-A in the Dodgers' and Yankees' farm systems from 1960 through 1964. After that, he served as a pitching coach for the Washington Senators, New York Mets, and Atlanta Braves, working closely with managers Gil Hodges, Yogi Berra, and Joe Torre.