cup final / final cup

[Mnemon]

Traffic is very dense on all routes into the city at the moment because of this evening’s football cup final.
English Collocation in Use book

Are they both idiomatic? “Cup final” and “final cup”? Or it would always have to be "cup final"!?

Thanks.

 

[emsr2d2]

Only "cup final" is correct. Take your cue from things like "the World Cup final" or "the FA Cup final". Sometimes you'll see "Final" (capitalised) when referring to the official name of the match.

 

[Tdol]

Final cup would be a last drink.

 

[emsr2d2]

Final cup would be a last drink.

Or the last drinking vessel for sale in a china shop. ;-)