Eisenstat debuted for his hometown Brooklyn Dodgers as a 19 year-old rookie in 1935. He pitched for three teams over eight big league seasons, mostly as a reliever, but occasionally as a spot starter. On October 2, 1938, when Bob Feller set a live-ball era single-game strikeout record by fanning 18 batters, his Indians still lost the game because Eisenstat earned a complete game win for Hank Greenberg and the Tigers. Earlier in the season, he pitched nine innings of shutout ball over both ends of a doubleheader while teammate Hank Greenberg hit three home runs, causing Mickey Cochrane to warn the two of them to stay in their rooms that night because “the Jews in Detroit are going crazy.” Eisenstat was traded to the Cleveland Indians the following season for future Hall-Of-Famer Earl Averill. In 1942, he enlisted in the Air Force, ending his playing career at the age of 26. After the Second World War, Eisenstat owned a hardware store in Shaker Heights, Ohio.