April – The 1979 Major League umpires strike begins with all umpires walking the picket lines, except two umpires (one from each league) who worked Opening Day with replacement and amateur umpires before leaving for the picket lines.
April 7 – The Houston Astros' Ken Forsch pitches a no-hitter against the Atlanta Braves in a 6–0 victory. At that time, it marks the earliest calendar date for a no-hitter in major league history, which stands until Hideo Nomo's no-hitter on April 4, 2001. This also makes him and Bob Forsch, who hurled a no-hitter in 1978, the first brothers in major league history to both pitch no-hit games during their careers.
May 15 – The 1979 Major League umpires strike is settled effective May 18. The umpires gain pay raises and additional vacation time by the addition of another crew, but eight minor league umpires who worked during the strike are promoted to the Major Leagues, causing dissention and ostracizing of the replacements whom the regular umpires referred to as "scabs".
May 28 – Texas Rangersfirst basemanMike Jorgensen is hit in the head by a pitch from Boston Red SoxpitcherAndy Hassler. Dave Roberts comes into the game to pinch run for Jorgensen, and Pat Putnam takes over as the Rangers' regular first baseman for the next month. Aside from a pinch-hit appearance on May 31, Jorgensen does not play again until July 1. After suffering headaches, it is discovered he has a small blood clot inside his head, which apparently caused a seizure and could have resulted in his early demise.
June 24 – In a 5–1 loss to the Rangers, Rickey Henderson debuts for the Oakland Athletics. He singles and doubles; the first of his over 3,000 career hits, and steals the first of his over 1,400 bases.
July 12 – The Detroit Tigers win the first game of a scheduled doubleheader against the Chicago White Sox, 4–1, on Disco Demolition Night at Chicago's Comiskey Park. Thousands of young fans swarm onto the field between the games, damaging the field and causing mayhem throughout the stadium. The White Sox are forced to forfeit the second game.
August 29 – In his first pitching appearance in the Major Leagues in his 11-year career, Kansas City Royals utility player Jerry Terrell entered the game in relief against the New York Yankees and got three outs on just three pitches in the ninth inning of a 17–3 loss.
September 24 – Pete Rose collects his 200th hit of the season, giving him ten seasons with at least 200 hits. This breaks the record set by Ty Cobb.
September 28 – Garry Templeton of the St. Louis Cardinals collects his 100th hit of the season while batting right-handed. Having already collected 100 hits while batting left-handed, Templeton is the first player in history to accomplish this. He had batted right-handed, exclusively, for the last week of the season to get the needed hits.
October 17 – In Game Seven of the World Series, Willie Stargell hits his third home run of the Series to send the Pittsburgh Pirates to their third straight win over the Baltimore Orioles, to win the World Series Championship. Stargell wins Series MVP honors. The Pirates came back from a deficit of 3 games-to-1.
November 13 – For the first time ever, there will be League co-MVPs as Keith Hernandez of the St. Louis Cardinals shares the National LeagueBaseball Most Valuable Player Award with Willie Stargell of the Pittsburgh Pirates. Stargell is the oldest person to win this award (since broken by Barry Bonds in 2004). The Pirates have thus won (or shared) all four "Most Valuable Player" awards for the season (All-Star Game, National League Championship Series, World Series, and National League regular season). This is the first such sweep in Major League history (Stargell had won the awards for the NLCS, World Series, and National League regular season, while teammate Dave Parker won the All-Star Game award).
November 26 – Third baseman John Castino, who batted .285 for the Minnesota Twins, and shortstop Alfredo Griffin, who hit .287 for the Toronto Blue Jays, tie for the American League Rookie of the Year Award, each receiving seven of the 28 votes. The deadlock precipitates a change in the voting system, effective in 1980.