Gamesmanship

noun

1. The use of aggressive or dubious tactics, such as psychological intimidation or disruption of concentration, to gain an advantage over one's opponent while still observing the rules in a sport or game.
2. The use of expedients or morally questionable acts to gain an advantage, as in politics.
3. The use of legal but unsporting tactics to gain an advantage over one’s opponent
4. the use of dubious (although not technically illegal) methods to win a game