In golf if your opponent's ball knocks your ball into the cup what is the ruling?

Answer 1

There are two scenarios;

1. On the green- If you and your opponent are on the green and he hits you ball and knocks it into the cup, or hits your ball at all, you replace your ball (to as near where it was before it was hit as possible) and he plays his from where it lies, and he shall receive a 2 shot penalty.

2. If your ball is on the green and your opponent is off the green and he hits yours, you replace your ball as near as possible to where you believe your ball was before he hit your ball. There is no penalty.