Once in a full moon... (Karl-Josef Hildenbrand/dpa/AFP/Getty Images) (KARL-JOSEF HILDENBRAND/AFP/Getty Images)

Much has been written already about Sports Equinoxes, those unicorn days on the calendar — all of them in October or November — when the NFL, NBA, NHL and MLB all have games. There have been 18 such days over the years, the last on Oct. 29, 2017.

The next is Thursday night, with a three-game NBA schedule, nine NHL games, the Broncos-Cardinals game in the NFL and Game 5 of the ALCS between the Red Sox and Astros. But wait, there’s more! Two college football games — Georgia State-Arkansas State and Stanford-Arizona State — also are on the docket, along with an MLS match between Real Salt Lake and New England.

All told, that’s six different sports or leagues on the schedule. According to enterprising Redditor imeanthisguy_really, that’s only happened one other time in our sporting history: Nov. 1, 2009. On that day, a Sunday, we had the following:

— A full NFL schedule during the day

— Seven NBA games

— Four NHL games

— World Series Game 4 between the Yankees and Phillies.

— Two MLS conference semifinals.

— And, in a rare Sunday night college football game, Central Florida defeated Marshall, 21-20. Back then, the NFL did not schedule a prime-time game on Sunday night if there was to be a World Series game on the same night (it would end this gentlemen’s agreement the next year). Thus, ESPN tried to fill the football void with a college game.

So if four sports is an Equinox, what do we call six sports? Hexinox? Sixinox? Seis-mic Anomaly?

Anyway, the next boring ol' Sports Equinox could take place Sunday, if the Astros can come back to force a Game 7. We also could get one on Oct. 28, should the World Series go five games.

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