In Major League Baseball, the right-handed pitcher appeared in ten games, nine in relief, for the 1951–52 New York Giants and the 1959 Baltimore Orioles.

He served in the United States Army during World War II in the Mediterranean and European theaters of operations[3] and signed with the hometown New York Giants in 1946.

He appeared in five more games, all as a relief pitcher, but was largely ineffective, allowing six hits, three walks, and four earned runs in four full innings of work.

In his American League debut on April 16, Bamberger was the starting pitcher against the defending World Champion New York Yankees at Memorial Stadium.

He never recorded a decision in the Majors, and compiled a 9.42 earned run average with 25 hits and ten bases on balls allowed, and three strikeouts, over 14+1⁄3 innings.

During that decade, he produced 18 twenty-game winners, including four for the 1971 American League champions: Jim Palmer, Mike Cuellar, Dave McNally and Pat Dobson.

Stating that a major goal was instilling a winning attitude, he added, "Last year the feeling I got was that we (the Orioles) should not lose to the Milwaukee Brewers.

Seven players hit double figures in home runs, and two (Larry Hisle, signed as a free agent, and Gorman Thomas) eclipsed the 30-homer mark.

He re-took the reins from interim pilot Buck Rodgers, but did not finish the season, resigning on September 7 after compiling a disappointing 47–45 win–loss record.

The 1982 Mets—still in the early stages of a rebuilding process that would produce the 1986 world championship—played at almost an identical pace (.401), led the National League in bases on balls and finished second-worst in team ERA.

"[11] A season and a half later, during the 1984–85 off-season, Dalton called Bamberger back into harness to attempt to revive the Brewers, who had plunged into the AL East basement in 1984.

The bright spot on the Brewers' staff was left-handed starting pitcher Teddy Higuera, who won 15 games as a rookie in 1985 and 20 more the following season.

Bamberger retired for a final time September 25, 1986, at age 63, turning the Brewers over to coach Tom Trebelhorn with nine games left in the season.