Clue: Champions not needing extra time, man — game of two halves, perhaps? (6)
Answer: CLICHE
Explanation: Definition: game of two halves, perhaps?
This one does not have the 'champions' as definition – indeed, they are thoroughly buried in the wordplay, A charade of C[e]L[t]IC ('champions') minus ('not needing') E ('extra' – a cricket reference for good measure) and T ('time') plus HE ('man'), with an indication by example ('perhaps') for "definition".