Bill Hohn has retired after 23 years as a major league umpire and been replaced by Todd Tichenor.
Hohn missed the 2011 season because of a back and neck issues. The 56-year-old worked the division series in 1996, 1998 and 2005, and the 1994 All-Star game. He was behind the plate for Hideo Nomo's no-hitter for the Los Angeles Dodgers at Colorado on Sept. 17, 1996.
The 35-year-old Tichenor, a member of the Triple-A Pacific Coast league staff since 2004, has worked 530 major league games as a fill-in umpire.
Major League Baseball said Thursday that umpires will wear patches this year honoring their late colleagues Marty Springstead and Harry Wendelstedt. Springstead was an AL umpire from 1966-85 and Wendelstedt an NL umpire from 1966-98.