Dan Osinski, American baseball player (d. 2013)
Daniel Osinski (November 17, 1933 – September 13, 2013), nicknamed "The Silencer", was an American Major League Baseball relief pitcher. The 6 ft 2 in (1.88 m), 195 pounds (88 kg) right-hander was signed by the Cleveland Indians as an amateur free agent before the 1952 season. He played for the Kansas City Athletics (1962), Los Angeles Angels (1962–1964), Milwaukee Braves (1965), Boston Red Sox (1966–1967), Chicago White Sox (1969), and Houston Astros (1970).

Born in Chicago, Osinski played baseball, football, and basketball in high school. He almost attended the United States Naval Academy on a football scholarship, but after flunking his physical, he chose instead to sign a contract with the Indians. He played minor league baseball with them for a few years but was plagued by mononucleosis, which he was diagnosed with in 1955. In 1957, Osinski was drafted by the United States Army, serving at Fort Campbell for two years. Unsure whether he should continue playing baseball or not, Osinski tried out with the White Sox in 1959 and was added to one of their minor league clubs. He focused on serving as a relief pitcher and made his major league debut with the Athletics in 1962. Though he did not last long with the Athletics, Osinski impressed the Angels' general manager while pitching for the minor league Portland Beavers. The Angels acquired him in a trade, and he helped give the team one of the best bullpens in the major leagues in 1962. In 1963, he made 16 starts for the club, though he also appeared in 31 games in relief. He posted a 3.48 earned run average (ERA) used mainly in relief in 1964, then was traded to Milwaukee.

Osinski posted a 2.82 ERA with the Braves in 1965 and also was asked by broadcaster Howard Cosell to demonstrate the spitball on national television. He was traded to the Red Sox in December, with whom he spent the next two seasons. Osinski had the lowest ERA of his career (2.54) in 1967 and pitched in two games in the 1967 World Series, which Boston lost to the St. Louis Cardinals in seven games. However, he was released during 1968 spring training and spent the season in the minor leagues. He earned a spot on the White Sox' roster in 1969 and posted a 3.56 ERA in 51 games. In 1970, he began the year with Houston but was assigned to the minor leagues after three games; he retired after the year. Following his baseball career, Osinski owned a restaurant as well a steel fabrication shop in Oak Forest, Illinois. Later, he sold cars in Sun City, Arizona. He died on September 13, 2013.