The idea of professional baseball league champions facing off against each other in a postseason series had been around since 1884, when the Providence Grays of the National League faced the New York Metropolitans of the American Association in a three-game series called “the Championship of the United States.”

The two leagues played similar series of between six to 16 games over the next several years until the American Association folded in 1891.

In 1900, the National League contracted from 12 teams to just eight. The next year, the American League was founded. In 1903, Pittsburgh Pirates owner Barney Dreyfuss challenged the American League champions, the Boston Americans, to a best-of-nine championship series that would bounce between Boston and Pittsburgh.

The Americans featured a dominant pitching staff led by Cy Young, who had finished the 1903 season at 28-9, and reliever Bill Dinneen, who led the league in saves.

Pittsburgh had dominated play in the National League for the past three seasons and was led by legendary shortstop Honus Wagner — who hit .355 that year and drove in 101 runs — and player/manager Fred Clarke, who batted .351.

The owner of the Pirates — in the back row of this photo showing both teams — was so pleased with the series he gave his share of ticket sales to the players, which made for a bonus of $1,316 each. This was more than the Boston players received for winning the series.

Fans in the cheap seats helped other fans gain admission for Game 3 on Saturday, Oct. 3.

Fans rushed the field before Game 3, gathering around the outfield and the diamond itself.

The Pirates, however, had ended the regular season with a bizarre series of incidents: Utility player Otto Krueger was beaned on Sept. 19 and had hardly played the rest of the season. Three days later, pitcher Ed Doheny left the team after exhibiting signs of paranoia. He was committed to an asylum where he would spend the rest of his life. In addition, Wagner suffered from a nagging leg injury and pitcher Sam Leever injured his shoulder while trap shooting.

The first three games of the series were held in Boston's Huntington Avenue Baseball Grounds. The Pirates and the Americans split the first two games, setting up a Saturday afternoon game that would officially draw 18,801 fans but, in fact, pulled in far more than that.

Seats were sold out hours before game time. Fence jumping was widespread. The crowd gathered around the playing surface began wandering onfield during pregame warmups.

“A surging, struggling, frantic crowd,” reported the Boston Post, “a sea of faces, a perspiring mass of humanity that fringed the fences, packed and jammed the stands, encircled the diamond and fought both police and players.”

Despite all this, the game began only 15 minutes late.