Greg Maddux has achieved a "Maddux" 13 times. A "Maddux" is a baseball game in which a pitcher pitches a shutout and does not allow any walks. This is a very difficult feat to accomplish, as it requires a pitcher to be both very good at throwing strikes and at preventing baserunners from advancing.
The Maddux Mastery Quiz: Untangling the Legendary Pitching Prowess of Greg Maddux