The following events and seasons scheduled to be played this year were cancelled or postponed to the following year as a result of the COVID-19 pandemic.
International Tournaments
2020 Summer Olympics: Postponed to 2021
European Cup: Cancelled
Grand Forks International: Cancelled
Haarlem Baseball Week: Cancelled
U-15 Baseball World Cup: Postponed
Women's Baseball World Cup: Postponed
World Baseball Classic: Postponed to March 2023
Domestic seasons
Minor League Baseball: All leagues cancelled.
Atlantic League of Professional Baseball: Cancelled
January 21 – Derek Jeter and Larry Walker are voted into the Baseball Hall of Fame by the Baseball Writers' Association of America. Jeter is named on all but one of the 397 votes cast or 99.7 percent; he misses joining 2019 inductee Mariano Rivera as unanimous Hall of Fame inductees. Meanwhile, Walker receives 304 votes, or 76.6 percent, in his 10th and final year on the ballot. Curt Schilling, Roger Clemens and Barry Bonds, all in their eighth year on the ballot, are the only other players to be named on 60 percent of the vote at 70.0, 61.0 and 60.7 respectively.
February 4 – The Philadelphia Phillies announce that they will retire Roy Halladay's number 34 on May 29, Halladay who was killed in a plane crash in November 2017 will be the ninth team member to have his number retired. It will be retired on the 10th anniversary of Halladay's perfect game.
February 26 – Due to the COVID-19 pandemic in Japan, NPB announced that their remaining 72 preseason games would be held behind closed doors and would not allow spectators to attend.
March
March 9 – NPB announces the postponement the March 20 start of the regular season because of coronavirus. The league ultimately set its return date for June 19.
March 12 – MLB cancelled the remaining spring training games and announced that the start of the regular season would be delayed indefinitely, due to the coronavirus pandemic.
June 23 – Major League Baseball announces its plan for a 60-game regular season, including several rule changes – most notably, the universal designated hitter. Schedules will include 40 games against division opponents and 20 games against the corresponding division in the other league, i.e. A.L. East vs. N.L. East. Players will receive a pro-rated salary of approximately 37 percent.
July 27 – Two games are postponed after as many as 13 members of the Miami Marlins test positive for COVID-19. The Marlins, who had just finished a three-game series in Philadelphia, were scheduled to return home to face the Baltimore Orioles. The Phillies' game against the New York Yankees is also postponed.
January 9 – David Glass, 85, owner of the Kansas City Royals from 2000 to 2019 who helped lead the team to back-to-back pennants in 2014 and 2015 while winning the World Series in the latter year.
February 11 – Katsuya Nomura, 84, Hall of Fame NPB catcher and manager who played for 26 seasons with three teams, primarily the Nankai Hawks, and managed four teams, including Yakult Swallows, who he led to three Japan Series titles.
February 15 – Tony Fernández, 57, a shortstop who played for seven major league baseball franchises and winning a championship with the Toronto Blue Jays in 1993 and currently ranks first in Blue Jays history in hits and games played.
February 28 – Johnny Antonelli, 89, left-handed pitcher primarily for the New York/San Francisco Giants who posted a 21-7 record with a National League best 2.30 ERA in 1954 while helping the team win the World Series that year.
March
March 26 – Jimmy Wynn, 78, outfielder nicknamed the "Toy Cannon" who hit 291 home runs in 15 major league seasons, who was most prominently known for his time with the Houston Astros.
April
April 6 – Al Kaline, 85, Hall of Fame right fielder who spent his entire 22-season career with the Detroit Tigers from 1953 to 1974, collecting 3,007 hits and hitting 399 home runs while winning 10 Gold Glove Awards along the way.
April 12 – Jim Frey, 88, manager who led the Kansas City Royals to their first pennant in 1980 and the 1984 Chicago Cubs to their first postseason appearance in 39 years and also led them to the playoffs again as their general manager five years later.
April 15 – Dámaso García, 63, second baseman who played 12 seasons in Major League Baseball with the New York Yankees, Toronto Blue Jays, Atlanta Braves and Montreal Expos.
May 14 – Bob Watson, 74, first baseman-outfielder who played 19 seasons in Major League Baseball with the Houston Astros, Boston Red Sox, New York Yankees and Atlanta Braves who also became the first African-American general manager to win a World Series in 1996 with the Yankees.
May 24 – Biff Pocoroba, 66, catcher who played 10 seasons in Major League Baseball, all with the Atlanta Braves.
June
June 10 – Claudell Washington, 65, outfielder who played 17 season in Major League Baseball with seven different teams; two-time All-Star and member of the World Series champion 1974 Oakland Athletics.
July
July 3 – Tyson Brummett, 35, pitcher who appeared in one game with the Philadelphia Phillies in 2012.