Head-to-head (6)
I believe the answer is:
versus
(Other definitions for versus that I've seen before include "Against (opponent)" , "Set against" , "playing" , "Against (another team)" , "Opposed to" .)
I believe the answer is:
versus
(Other definitions for versus that I've seen before include "Against (opponent)" , "Set against" , "playing" , "Against (another team)" , "Opposed to" .)