Salary caps to shootouts: how US soccer could transform the game

The US was the first country to introduce substitutions and the backpass law. Here are five other innovations worthy of consideration for a wider rollout

Soccer in the US has continually experimented over the years, trying to find a balance between the game experienced around the world and serving up a uniquely Americanized product to its domestic audience, with rules echoing those found in the nation's major sports leagues.

Some changes were revolutionary and stuck around - a rudimentary form of the backpass rule was an innovation of the North American Soccer League in the 1980s, for example, long before it was adopted throughout the game in 1992; likewise the use of substitutes, which was pioneered by the American Soccer League in the 1920s more than three decades before the idea was written into the laws of the game internationally.