Originally signed by the Cleveland Indians, Fosnow pitched a no-hit game on August 20, 1959, his first professional season, in the Class D Alabama–Florida League.
[1] He was eventually acquired by the Twins' farm system and was recalled by Minnesota from the Triple-A Atlanta Crackers in the middle of the 1964 season.
In seven appearances and 10+2⁄3 innings pitched, all in relief, Fosnow sported a 0–1 win–loss record and a poor 10.64 earned run average.
However, he earned a job in the 1965 Twins' bullpen coming out of spring training and won his first Major League game on Opening Day, April 12, pitching two scoreless innings against the New York Yankees in relief of Jim Kaat.
But he was sent to the Triple-A Denver Bears after his last MLB game on July 16, 1965, and did not appear on the Twins' World Series roster.