The Wikipedia listing for Gotham City indicates that on the animated series, there was a Gotham Knights football team.

In Knox' version of Gotham, I have relocated the New York football Giants (as well as the baseball Mets) to Gotham. I root for them, thus Knox does.

And while the DCU - like a lot of SF worlds - seems to have a lot more references to baseball than to any other sport, Guy Gardner and Booster Gold were college football stars and Clark Kent (in some continuities) was a high school football star.