The left-handed pitcher appeared in 88 games in Major League Baseball, all but one in relief, over all or parts of five seasons (1959–62; 1964) for the Pittsburgh Pirates and Washington Senators.

A native and longtime resident of the Titusville section of Hopewell Township, Mercer County, New Jersey, he was listed as 6 feet 4 inches (1.93 m) tall and 190 pounds (86 kg).

Fred Green signed with the Pirates in 1952 and advanced through their farm system, missing 1957 to perform military service in the United States Army.

After beginning 1959 for the Pirate varsity, then making one appearance in July, Pittsburgh called him up from Triple-A Columbus in August 1959 for an extended stay in the majors.

In three appearances, all lopsided Pirate losses, Green surrendered 11 hits and ten earned runs in only four full innings of work—an ERA of 22.50.