After spending one season with the organization, he was traded to the Cincinnati Reds in October 1951, the same month he drafted into the US Army.

[4] During his first year with the team, he finished with a 3–6 win–loss record and a 5.06 earned run average (ERA) in 80 innings pitched.

His performance improved in his second season, with a 14–7 record, a 3.18 ERA, and 213 strikeouts over 201 innings,[4] helping the Giants secure the pennant.

Although Acker finished the 1950 season with fewer wins (6), he managed to lower his ERA to 3.07 across 132 innings pitched.

[4] The Smokies won the pennant,[2] and he was subsequently selected by the Buffalo Bisons in the minor league draft at the end of the year.

He rebounded in 1955 with the Nashville Volunteers, where he improved his win–loss record (11–8) and ERA (3.26), and made 10 additional starts compared to the previous season.

He started 7 of the 29 games in which he pitched,[1] and recorded the only shutout of his major league career against the Philadelphia Phillies on September 19.

[9] He compiled a 10–5 record, a 4.97 ERA, and 67 strikeouts in 108+2⁄3 innings pitched, making six starts and saving four games that season.

[4] He was unconditionally released after he declined a move to the Dallas Rangers of the American Association, given his reluctance to displace his family across the country.

[2] After retiring from baseball, Acker returned home to Bergen County, New Jersey, constructed a house in Wyckoff, and was employed by a trucking company.

[2] He started working for the New Jersey Sports and Exposition Authority at the Meadowlands Racetrack shortly after the facility opened in 1976, first as a mutuel clerk, then as a supervisor.