Scott began umpiring at age 15 and entered the minor leagues in 1981, eventually working his way up to the Triple-A American Association. He umpired a single major league game during the 1985 MLB season, making his debut in an August 19 game between the Kansas City Royals and Detroit Tigers. Scott became a full-time MLB umpire in 1986, working 116 games that season. Scott worked a total of 3,897 regular season games, 91 post-season games, and issued 90 ejections in his MLB career.