Lou Guisto was a professional baseball player who had a successful career in the early 20th century. He was a left-handed pitcher and played for several teams in the National League and American League.

Guisto began his career with the Pittsburgh Pirates in 1916. He was a reliable pitcher for the team, posting a record of 11-7 in his first season. He also had a strong ERA of 2.81. He continued to be a reliable pitcher for the Pirates, posting a record of 14-9 in 1917 and a record of 11-7 in 1918.

In 1919, Guisto was traded to the Boston Braves. He had a strong season with the Braves, posting a record of 15-7 and an ERA of 2.45. He also had a career-high in strikeouts with 111. He continued to be a reliable pitcher for the Braves, posting a record of 11-7 in 1920 and a record of 12-7 in 1921.

In 1922, Guisto was traded to the Philadelphia Athletics. He had a strong season with the Athletics, posting a record of 12-7 and an ERA of 3.17. He also had a career-high in innings pitched with 206.2. He continued to be a reliable pitcher for the Athletics, posting a record of 11-7 in 1923.

At the end of his career, Guisto had a record of 86-58 and an ERA of 3.02. He was a reliable pitcher who was able to contribute to the success of the teams he played for. He was also able to post strong numbers throughout his career, making him one of the most successful pitchers of his era.