Well That's Not Cool...
Walking on somebody’s line before they putt in golf (the_buddhaverse)
Or, in casual conversation on the first tee, ask: “I’ve always wondered, do you like to inhale or exhale during your swing?”
That’ll have their game screwed up for a while.(hipsterhank)
For those not familiar with the biggest intenational incident between Australia and NZ I give you underarm bowling in cricket. Trevor Chappell bowled the last ball of a limited over match underarm to make it impossible for the batsman to score a 6 to tie. This move is now illegal but not when it occurred it wasn’t. (smileedude)
In snooker, the player Ronnie O’Sullivan was publicly criticised and derided by his fellow professionals for switching hands mid-game and playing left-handed. It was viewed as an enormous sign of disrespect to an opponent he was already comfortably beating.
He is in fact fully ambidextrous and since then has played fluently left- or right-handed depending on which is positionally easier for the shot. Now it’s just viewed as an example of his exceptional skill and commitment to the game, having trained with both hands to championship-winning standard. But the first time he did it, it was really damaging to his profile.(ArtOfFailure)