Laz Díaz

Laz Díaz (born October 12, 1963) is a professional Major League Baseball (MLB) umpire. He wears uniform number 63. Díaz has officiated in the National League (NL) from 1995-1999, and MLB since 2000. He has umpired in multiple high-profile games, including the World Series, League Championship Series, Division Series, and All-Star Game. Díaz is known for his assertive strike zone and occasionally demonstrative calls. His performance has been subject to scrutiny and debate among baseball fans and analysts. He was promoted to crew chief status in 2016.