Nestor George Chylak, Jr. (May 11, 1922 - February 17, 1982) was an American umpire in Major League Baseball who worked in the American League from 1954 to 1978. He umpired in three ALCS (1969, 1972, 1973), serving as crew chief in 1969 and 1973. He also called five World Series (1957, 1960, 1966, 1971, 1977), serving as the crew chief in 1971 (in which he called balls and strikes in the decisive Game 7) and 1977. He also worked in six All-Star Games: 1957, 1960 (both games), 1964, 1973 and 1978, calling balls and strikes in the second 1960 game and in 1973. He was born in Olyphant, Pennsylvania of Ukrainian descent, and attended the University of Scranton, where he studied engineering. During World War II, he served in the Army in Europe; in the Battle of the Bulge he was wounded by shrapnel from an exploding shell and was hospitalized for eight weeks with an injury that nearly cost him his sight. He earned both the Silver Star and Purple Heart during his service.
Contributions by MisfitToys, Twelsht, and Cydebot.