fluke

A fluke is the right result reached by the wrong route — the outcome was real, the method an accident. That is why it sounds modest about your own win and rude about somebody else's. It came out of billiards slang in the 1850s, for exactly this kind of shot. In the animation, a golfer's bad swing sends the ball sideways off a rake; he lands flat on his back — and the ball drops in the hole.