In baseball, a no-hitter is a game in which a team was not able to record a single hit. Major League Baseball (MLB) officially defines a no-hitter as a completed game in which a team that batted in at least nine innings recorded no hits. A pitcher who prevents the opposing team from achieving a hit is said to have "thrown a no-hitter". This is a rare accomplishment for a pitcher or pitching staff: only 303 have been thrown in MLB history since 1876, an average of about two per year. In most cases in MLB, no-hitters are recorded by a single pitcher who throws a complete game; one thrown by two or more pitchers is a combined no-hitter. The most recent major league no-hitter by a single pitcher was thrown on September 1, 2019, by Justin Verlander of the Houston Astros against the Toronto Blue Jays at Rogers Centre. The most recent combined no-hitter was thrown on August 3, 2019 by Aaron Sanchez, Will Harris, Joe Biagini, and Chris Devenski of the Astros against the Seattle Mariners at Minute Maid Park.