Definition of off (or on) one's game in US English:

off (or on) one's game

phrase

  • Playing badly (or well).

    • ‘When he's on his game, he can play most pucks without flinching.’
    • ‘When he was on his game, he was a tremendous offensive talent.’
    • ‘There times when you get scared, but that keeps you on your game.’
    • ‘Owen, 21, a former Bury Boys' champion from Breightmet, had already played in a couple of Tamsel Tour events this season, conceded that he was not on his game.’
    • ‘‘We had too many players off their game at the same time against him,’ he said.’
    • ‘There isn't room for that, and you have to be on your game at all times.’
    • ‘The crew chief needs to make sure he is on his game.’
    • ‘They can take bad penalties and, despite their excellent penalty killing, get off their game.’
    • ‘On nights when the Kings are on their game, the talk of how the NBA has become hard to watch should be muted.’
    • ‘He can steal a playoff series if he's on his game, but the Lightning never is sure what it is going to get from him.’