Oh, Wikipedia (or ESPN.com's readers)

Tim Tscida's page

Tschida is known for his quality work and is a well-respected umpire, but is probably best known for his massive blunder in blowing a call in the 1999 American League Championship Series in which Chuck Knoblauch's applied a "phantom tag" to Jose Offerman. The call was ranked the worst call in sports history by readers of ESPN.com.