1920 in sports

Baseball

January 3 – Boston Red Sox owner Harry Frazee sells Babe Ruth to the New York Yankees for $125,000 and a $350,000 loan, beginning "The curse of the Bambino". This was the prelude to an extraordinary Major League season during which the Bambino would hit 54 home runs, Cleveland shortstop Ray Chapman would be killed by a pitch from Carl Mays, and Eddie Cicotte and Shoeless Joe Jackson would confess to their roles in the Black Sox scandal.
February 13 – The Negro National League of baseball is formed.
May 2 – The first game of the Negro National League baseball is played in Indianapolis, Indiana.
August 16 – Ray Chapman of the Cleveland Indians is hit in his head and fatally wounded with a fastball from Carl Mays of the New York Yankees. Chapman will die early the next day, becoming the only person to ever die from a major league baseball game (as of 2004).

Victorian Football League – Richmond wins the 24th VFL Premiership (Richmond 7.10 (52) d Collingwood 5.5 (35))

1920 Summer Olympics takes place in Antwerp, Belgium
- The 1916 Summer Olympics were due to take place in Berlin, Germany, but were cancelled, due to World War I. Following the war, the Olympics were awarded to Antwerp to "honor the suffering of the Belgian people".
- United States wins the most medals (95), and the most gold medals (41).

The National Football League is formed as the American Professional Football Association in Canton, Ohio on September 17. The Akron Pros finished undefeated and are the first champions of the league.