The two hours after the USA vs. the World competition ends are the classic example of a dénouement.
Sure, there are plenty of races, and a lot of the fans stick around for them. They even get pretty excited for the high school boy's 4x400-meter Championship of America.
But it's pretty clear that everyone, from fans to administrators, is exhausted. So as the infield slowly clears out, the mood becomes a lot more laid-back.
A lot of people sit on the infield instead of standing, and those who move around do so a lot more slowly than they did before. It's clear that things are coming to an end,