Philadelphia was central to the formation of the first two pro soccer leagues in the US, the National League baseball-backed American League of Professional Football, and the American Association of Professional Football, which played its first games before, and outlived, the ALPF.
This weekend, the US faces Mexico in a one-off game to reach the 2017 Confederations Cup. The first time the US played a one-off playoff game was also against Mexico in 1934 with a World Cup berth at stake.
A look at the founding of the EPSA, originally known as the Foot Ball Association of Eastern Pennsylvania and District, in April, 1913, six days after the founding of the United States of America Football Association, known today as the US Soccer Federation.
On May 3, 1936, Philadelphia German Americans became the first amateur team, and the first team from the city of Philadelphia, to win the US Open Cup.
The 1934 US World Cup team had a Philadelphia manager and coach and also included five players from the Philadelphia German Americans ASL team.
When Toronto faces the Union at PPL Park on Saturday, they will be following in the footsteps of the first Toronto team to play in Philadelphia in 1905.