The White Sox had portrayed Callison as the "next Mickey Mantle". That label was pretty big for anyone to carry around and Callison struggled with it in Chicago. Callison, who signed with Chicago right out of high school in Qualls, Oklahoma, was with the 1959 pennant winning White Sox team at the start of 1959. By the time July arrived, Callison was hitting just .179 and went back to the minors for more work. Still, the Mantle comparisons blossomed, perhaps spurred on by the fact that Mantle too had struggled in his early major league days.
Callison arrived in Philadelphia, where his reputation had already arrived. Phillies fans too were told that the team had acquired the next Mickey Mantle, so Callison wouldn't soon shake the label. After hitting just 18 homeruns and hitting a combined .264 in his first two seasons in Philadelphia, fans were beginning to wonder if Callison would ever reach the potential that they had been told about. In 1962, Callison finally started to show both the power and some ability to hit for a higher average when he clubbed 23 homeruns and hit .300 on the season. Manager Gene Mauch sat Callison on the final day of the season to be sure to preserve his .300 average. Mauch also talked about Callison's potential and how he thought hitting .300 would become almost routine for Callison. Unknowingly, Mauch had done Callison a great disservice.
While Callison would top his homerun total of 23 in each of the following three seasons, he would never again hit .300. In fact, Callison's first two seasons were almost exactly what his career numbers worked out to be. At the end of his career, Callison had hit a total of 226 homeruns and finished as a career .264 hitter.
In the early ‘60s, Callison was one of the better young players in the game. In 1964, he played a major part in getting the Phillies close to the pennant when he hit 31 homeruns and finished the season with a .274 average. He also drove in 104 runs and scored 101. The season included a momentous homerun in the bottom of the ninth inning of the All-Star Game to give the National League a 7-4 win. When the season ended, Callison had finished second in the MVP voting trailing only Ken Boyer of the Cardinals. It's likely that if the Cardinals hadn't passed the Phillies in the standings, the MVP would have been Callison and not Boyer.
Unfortunately, Callison's power would last just one more season. He hit a career high 32 homeruns with 101 RBI in 1965 and his power just evaporated into thin air from that point. In four more seasons with the Phillies, Callison hit just 55 homeruns and drove in a total of 223 runs.
Callison's defensive abilities have often been overlooked. He led the league in outfield assists for four straight seasons during the early ‘60s.
After the 1969 season, Callison found himself back in Chicago. This time, it was with the Cubs, who sent Dick Selma and Oscar Gamble to the Phillies for a 30 year old Callison. Two years later, Callison was traded to the Yankees and his career ended during the '73 season when he was released, hitting just .176.