Walls graduated from Pasadena High School and attended Pasadena City College. He signed with the Pirates in 1951. In 1956, his first full MLB season, Walls batted.274 with 11 triples, 11 home runs and 54 RBIs. On July 2, 1957, Walls—by this time a member of the Cubs—hit for the cycle in an 8–6 loss to Cincinnati at Wrigley Field. It was the highlight of a poor sophomore season for Walls, with his batting average dropping to.237 in 125 games played. The next season, 1958, proved to be Walls' best year. Playing as the Cubs' regular right fielder, Walls reached career highs in hits, home runs, RBIs and batting average in 136 games played. On April 24, against the newly-relocated Dodgers at the Los Angeles Memorial Coliseum, minutes down the freeway from his hometown of Pasadena, Walls hit three home runs and had eight RBIs in a 15–2 Chicago rout. Selected to the National League All-Star team as a reserve, he pinch hit for the Pirates' Bob Skinner in the seventh inning and grounded out against Billy O'Dell. Walls stayed in the game to play left field, but that was his only plate appearance as the American League won, 4–3, at Baltimore's Memorial Stadium. Walls' production declined in 1959, and after that season his last five years in MLB were spent as a utility player, playing infield, outfield, and pinch hitting. Walls delivered 45 hits in 176 at bats during his career as a pinch hitter, and was particularly effective in 1962, going 13-for-27 in the pinch for the Dodgers, who ended the 162-game season in a tie with the San Francisco Giants, necessitating a best-of-three playoff round. Walls played all three games of the 1962 National League tie-breaker series, including a Game 1 start at first base, and contributed a pinch double in Game 2, driving home three RBIs to spark a crucial, seven-run Los Angeles rally. By winning, 8–7, the Dodgers staved off elimination and extended the series to a decisive third contest. The next day, however, the Dodgers fell to the Giants in the ninth and final inning. Walls, pinch hitting for Larry Burright, made the final out, lining out to center fielder Willie Mays. The following year, Walls was a member of the world champion Dodgers, but did not appear in his club's four-game sweep of the New York Yankees in the 1963 World Series. In 902 total games played over ten National League seasons, Walls collected 670 hits, with 88 doubles, 31 triples and 66 homers. After spending 1965 playing baseball in Japan, Walls retired as an active player.
Later career
A decade and a half after his last appearance for the Dodgers, Walls returned to MLB as a coach for the Oakland Athletics and Yankees, working primarily for Billy Martin, a teammate on the 1960 Reds. He also worked as a minor league manager. He died in Los Angeles at the age of 60 after suffering from liver disease.
