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From BR Bullpen
A no-hitter is a game in which a pitcher, or pitchers, gives up no hits. The term is most often used to describe a game in which a single pitcher throws a complete game of at least 9 innings (27 outs) without giving up a hit.
A no-hitter does not imply that the opposing team has not reached base, however, since it is possible to reach base without a hit, either by a base-on-balls, a hit-by-pitch or error. It also does not imply a shutout or even a win, although it is extremely uncommon for a pitcher, or pitchers, to throw a no-hitter and lose the game. Any no-hitter that goes nine innings but is forced to extra innings can only remain a no-hitter if no hits are given up in the extra frames.
A perfect game is a no-hitter in which no runner is allowed to reach base, whether by hit, base-on-balls, hit-by-pitch or error.
 Major League Baseball
The current Major League Baseball definition, since 1991, of a no-hitter is "a game in which a pitcher, or pitchers, gives up no hits while pitching at least nine innings. A pitcher may give up a run or runs so long as he pitches nine innings or more and does not give up a hit."
Prior to 1991, Major League Baseball defined a no-hitter as "an official game in which a pitcher, or pitchers, gives up no hits." After the definition changed 31 "no-hitters" were erased.
No-hitters occur at a rate of about three per season over the course of Major League Baseball history. The most no-hitters in a single season was 1884 in which twelve were thrown, followed by 1990 with 9 and 1991 with 8. However, since the redefinition the totals for each season have been reduced to eight in 1884 and seven in 1991, 1990 and 2012.
Of the 288 no-hitters in Major League Baseball history, 23 have been perfect games (counting the two post-season no-hitters, and including Don Larsen's perfect game).
The pitcher who holds the record for the most no-hitters, with seven in his career, is Nolan Ryan. His first two came with the 1973 California Angels, one on May 15th and the other on July 15th. He had two more with the Angels; the third on September 28, 1974 and the fourth June 1, 1975. He threw his fifth no-hitter with the Houston Astros on September 26, 1981, breaking Sandy Koufax's record. His sixth and seventh no-hitters came with the Texas Rangers, the sixth on June 11, 1990 and the last on May 1, 1991 at the age 44, making him the oldest pitcher to toss a no-hitter.
There have been eleven combined no-hitters. The first was on June 23, 1917, with Babe Ruth as the starting pitcher for the Boston Red Sox against the Washington Senators. After walking the first batter of the game (Eddie Foster), Ruth was ejected for arguing with an umpire. Ernie Shore came in to relieve Ruth and after Foster was caught stealing, he retired the next 26 batters. For 74 years, Major League Baseball recognized Shore's feat as a perfect game as he technically achieved 27 consecutive outs with no batter reaching base (the runner caught stealing is counted as being an "out"). However, after stricter no-hitter definitions established in 1991, the game became a combined no-hitter.
The record for pitchers used in a combined no-hitter is six, set by the Houston Astros against the New York Yankees on June 11, 2003 when Roy Oswalt, Peter Munro, Kirk Saarloos, Brad Lidge, Octavio Dotel, and Billy Wagner shut down the "Bronx Bombers." The Seattle Mariners repeated the feat on June 8, 2012, also in an interleague game, against the Los Angeles Dodgers. In that game, Kevin Millwood, Charlie Furbush, Stephen Pryor, Lucas Luetge, Brandon League and Tom Wilhelmsen were the pitchers involved.
A game that is a no-hitter through 9 innings may be lost in extra innings. In 1917, Fred Toney of the Cincinnati Reds and Hippo Vaughn of the Chicago Cubs each threw nine innings of no-hit ball; the only time in baseball history that neither team has had a hit through nine innings. The Reds got two hits in the top of the 10th and scored a run; in the bottom of the frame Toney retired the side and recorded a ten-inning no-hitter.
There have been two instances when a pitcher has had a perfect game through nine frames, but then lost it in extra innings. In 1959, Harvey Haddix of the Pittsburgh Pirates pitched twelve perfect innings before losing the no-hitter and the game to the Milwaukee Braves in the 13th. On June 3, 1995, Pedro Martínez of the Montréal Expos gave up a double to Bip Roberts of the San Diego Padres to lead off the 10th after being perfect for nine innings. Mel Rojas came on and retired the next three batters for a combined 1 - 0, one-hit win.
There have also been two games in which a team has had a no-hitter thrown for them but has lost. The first occurred on April 23, 1964, as Ken Johnson of the Houston Colt .45's was beaten 1 - 0 by the Cincinnati Reds. In the top of the 9th, Johnson allowed a run to score on two errors, and in the bottom of the frame the Houston bats came up empty. He remains the only pitcher to lose a complete game nine-inning no-hitter.
Three years later, in 1967, Steve Barber and Stu Miller of the Baltimore Orioles pitched a combined no-hitter, but lost, 2 - 1, to the Detroit Tigers. In the top of the 9th, two runs were scored on three walks, a wild pitch, and two errors.
 Unusual Feats
- In June 1938, Johnny Vander Meer of the Cincinnati Reds accomplished what no other pitcher has managed to duplicate (in Major League Baseball, see Aquino Abreu below), by pitching no-hitters in two consecutive appearances. On June 11 of that year, he threw a no-hitter against the Boston Bees, in his very next start, June 15, he threw a no-hitter against the Brooklyn Dodgers, in the first night game at Ebbets Field. Including his two starts before and after the no-hitters, Vander Meer pitched a total of 21 1/3 no-hit innings over four games. This record is considered to be nearly unbreakable, since to do so a pitcher would have to throw three consecutive no-hitters. The pitcher who has come the closest to matching Vander Meer's feat was Ewell Blackwell of the 1947 Reds, who had a no-hitter broken up with one out in the ninth against Brooklyn on June 22 of that year, four days after no-hitting the Boston Braves 6-0.
- On October 8, 1956, Don Larsen became the only person to throw a no-hitter (and perfect game) during a World Series game. Larsen's no-hitter was the only one thrown in any postseason game. Roy Halladay threw the second postseason no-hitter for the Philadephia Phillies, on October 6, 2010. Thirty years before Larsen's gem, Claude "Red" Grier threw a no-hitter on October 3 in the 1926 Colored World Series, walking six and fanning eight.
- On Opening Day 1940 (April 16) Bob Feller of the Cleveland Indians no-hit the Chicago White Sox; it remains the only recognized Major League Opening Day no-hitter to date, though Leon Day of the Newark Eagles matched the feat in the Negro National League on May 5 1946.
- In 1953, Bobo Holloman of the St. Louis Browns pitched a no-hitter in his first major league start; although it was not his first major league game.
- On June 29, 1990 two no-hitters were thrown within hours of each other. Dave Stewart of the Oakland Athletics pitched a no-hitter in Toronto against the Toronto Blue Jays. Later in the day, Los Angeles Dodger Fernando Valenzuela pitched a no-hitter in at home against the St. Louis Cardinals.
- In September 1968 no-hitters were thrown in back-to-back games during a series between two teams. On September 17, 1968, Gaylord Perry of the San Francisco Giants no-hit the St. Louis Cardinals, 1-0, at Candlestick Park. On the following day, Ray Washburn returned the favor for the Cardinals winning against the Giants, 2-0. The feat was repeated the next season when Jim Maloney of the Reds blanked the Astros 10-0 on April 30 at Crosley Field, only to have Don Wilson no-hit the Reds on the following night.
- Bob Forsch and Ken Forsch are the only pair of brothers to both pitch official no-hitters. Bob pitched two no-hitters while with the St. Louis Cardinals, the first in 1978 and the second in 1983. Ken pitched one for the Houston Astros in 1979. Brothers Pascual Pérez and Melido Pérez both pitched rain-shortened, unofficial no-hitters; Pascual in five innings for the 1988 Montreal Expos and Melido in six innings for the 1990 Chicago White Sox.
- In 1969, Bill Stoneman pitched a no-hitter for the Montréal Expos in only the ninth game of the franchise's existence, the quickest of any team.
- Chicago White Sox catcher Ray Schalk and Boston Red Sox catcher Jason Varitek caught the most no-hitters in their careers with four each. Schalk was the backstop for Jim Scott and Joe Benz in 1914, Eddie Cicotte in 1917 and for Charlie Robertson's perfect game in 1922. Scott's no-hitter is no longer considered "official" as he surrendered two hits in 10th. Varitek was the backstop for Jon Lester in 2008, Clay Buchholz in 2007, Derek Lowe in 2002, and Hideo Nomo in 2001, all "official" games.
- 12 catchers have caught three no-hitters: Alan Ashby, Bill Carrigan, Charles Johnson, Del Crandall, Ed McFarland, Jeff Torborg, Jim Hegan, Luke Sewell, Ray Schalk, Roy Campanella, Silver Flint, Val Picinich. Yogi Berra is included if postseason games are counted as well.
- Umpire Silk O'Loughlin presided over more no-hitters, six, than any other umpire. Bill Dineen, Bill Klem, and Harry Wendelstedt each umpired five games.
 Negro League Baseball
There were at least 30 confirmed nine-inning no-hitters between recognized Negro League teams, including one in the 1926 Colored World Series. While there were several no-hitters by great Negro pitchers recorded against lesser semi-pro competition (Rube Foster is known to have thrown four), the first no-hitter by a Negro pitcher against a bona fide top Negro team was by Frank Wickware of the Chicago American Giants against the Indianapolis ABCs) in 1914; the last nine-inning Negro League no-hitter was by Leon Day in 1946. Bill Gatewood, Phil Cockrell, and Satchel Paige each pitched two confirmed no-hitters in Negro League and pre-league competition.
Webster McDonald and Sug Cornelius both hold the odd distinction of having thrown no-hitters that were broken up in extra innings, and having been the losing pitchers in another man's no-hitter, McDonald losing to Red Grier in the 1926 Colored World Series and Cornelius losing to Hall of Famer Hilton Smith in 1937.
In August 1927 Willie Powell and Webster McDonald of the Chicago American Giants just missed throwing back-to-back no-hitters against the same opponent. Powell no-hit the Memphis Red Sox 5-0 on August 14, and McDonald followed the next day with a 9-inning no-hitter that was tied 1-1 after nine; McDonald lost the no-hitter in the 9th, and lost the game 2-1 in the 10th.
 Nippon Professional Baseball
There have been 90 no-hitters thrown in Nippon Professional Baseball. The first no-hitter was thrown by Eiji Sawamura on September 25, 1936 when the Tokyo Kyojin beat the Osaka Tigers 1 - 0. Two pitchers, Sawamura and Yoshiro Sotokoba, have thrown three no-hitters, an NPB record. Hideo Fujimoto threw the first perfect game on June 28, 1950 for the Yomiuri Giants versus the Nishi-Nippon Pirates, winning 4 - 0.
 Cuban National League
There have been 57 no-hitters thrown in the Cuban National League through March 14, 2012.
In January 1966 right-hander Aquino Abreu of Centrales pitched back-to-back no-hitters, matching the feat accomplished by major-leaguer Johnny Vander Meer. On January 16 against Occidentales at Estadio Augusto César Sandino he won 10 - 0; nine days later against Industriales at Estadio Latinoamericano he won 9 - 0.
 World Baseball Classic
On March 1, 2006, Shairon Martis playing for The Netherlands in the World Baseball Classic threw a seven-inning no-hitter versus Panama at Hiram Bithorn Stadium in San Juan, Puerto Rico. The game ended by a mercy rule with the Dutch winning 10 - 0. Martis accomplished the feat in 65 pitches, the limit for the WBC first round. The game ended with a double play by the last batter that Martis could face.
 Lists of No-Hitters
- List of Major League Baseball Sanctioned No-Hitters
- List of Major League Baseball "Near" No-Hitters
- List of Minor League No-Hitters
- List of Negro Leagues No-Hitters
- List of Nippon Professional Baseball No-Hitters
- List of Cuban National League No-Hitters
- List of Chinese Professional Baseball League No-Hitters
 Further Reading
- Rebecca Sichel, Uri Carl and Bruce Bukiet: "Modeling Perfect Games and No-Hitters in Baseball", in The Baseball Research Journal, SABR, Volume 40, Number 1 (Spring 2011), pp. 58-65.