I’m probably being whooshed here, but the NHL is the National Hockey League – the highest profession league for hockey.
Contractual obligation first; the Rangers and Knicks had to compete with the circus at least until the 70s. However, MSG owns both clubs, so they make the decision.
I don’t know if this counts, but back in the days when MMA events were still called “no holds barred” (mid 90s) and were not sanctioned, a PPV event was switched at the last minute (the day of the event). The event was supposed to take place in Canada but some of the fighters were denied entry into the country by customs. So they moved the event to some Indian reservation (in NY maybe) and held it there instead.
In January 1978 the roof of the Hartford Civic Center collapsed during a snowstorm a few hours after a New England Whalers hockey game. The damage to the arena was so severe the team had to relocate to Springfield, Mass. until 1980.
Along those same lines, if memory serves because I don’t have a cite, back in the 1970s when NFL teams frequently shared playing facilities with MLB teams, the NFL tried to schedule games that might interfere with MLB playoff games as interdivisional contests, so that the NFL teams could flip flop their games.
Not the pros, but the 1942 Rose Bowl, originally planed to take place on Jan 1,1942, in Pasadena, CA, was instead played in Durham, North Carolina. No points for guessing why.
Nope, still not ringing a bell…