He was considered the best pitcher in the history of Clarkson University, a small engineering school in northwestern New York State. Born in Rome, New York in 1918, his real first name was Emerson but his Clarkson coach started calling him “Steve” instead because it was easier to both say and remember. Roser had a choice to make in 1940. He could either finish his senior year at Clarkson or sign a contract with the Yankees. He signed the contract and spent the next four years pitching his way up New York’s minor league ladder.
Joe McCarthy put him on the parent club’s roster for the first time in 1944, and Roser pitched well enough to stick around the entire season. His big league debut came on May 5th of that year against the Red Sox. He relieved starter Atley Donald in the top of the fifth inning with the score tied and finished the game, which the Yankees won, earning him his first career victory. He got his first career start two months later and earned a complete game 8-2 win over the Tigers. He would finish that first season with a 4-3 record and one save and he earned good marks from McCarthy who kept Roser on the roster the following season.
In 1946, his slow start combined with the mass return of Yankee pitching talent from military service in World War II got the right-hander sold to the Boston Braves in early May. He pitched OK but sparingly in Beantown for a few weeks and then spent the second half of the season with the Braves triple A team in Indianapolis. Despite a good record in Indy, he failed to make the Braves roster the following spring and when he pitched poorly during the 1947 season in the minors, he quit the game for good. Roser returned to upstate New York where he and his wife opened a sporting goods store and a restaurant. Roser passed away in 2002.