Green’s Dictionary of Slang

boxing; thus coring match n., a boxing match.

1936		J. Curtis Gilt Kid 281: There was a bit of a coring match when they claimed me.
1961		(con. 1920s) J. Sparks Burglar to the Nobility 87: He was reluctant to meet me in a coring-match or punch-up.
1961		(con. 1920s) J. Sparks Burglar to the Nobility 88: The chaplain went on thundering ‘Lead, Kindly Light’ with Speedles and me coring away around his feet.