play the ball and not the man

(sports) To attack the ball instead of an opponent who is usually controlling the ball. Often considered a positive action, and sometimes a requirement not to concede a penalty.

(by extension, idiomatic, colloquial) To object to someone's argument by attacking the argument itself instead of them or a facet of their personality; to avoid or make the opposite of an ad hominem attack. Usually considered a positive action, and an avoidance of a fallacious argumentative technique. Often used in comparison to play the man and not the ball.