Crossword Genius

Group of sports clubs that compete for a championship (6)

Ross

I believe the answer is:

league

(Other definitions for league that I've seen before include "Association of states or sports teams" , "some mileage?" , "About five kilometres" , "The alliance extends over three nautical miles." , "Association of sports teams to organise matches" .)

I've seen this clue in The Irish Times.
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