[McLovin]

Originally Posted by blakesq

Thanks MCLOVIN, you correclty pointed out that I was wrong, but your answer also is incorrect. A let is only called if it is UNCLEAR whether the correct ball was played. If the returner hits the wrong ball as a winner, but it is clear later that he played the wrong ball, then no let, he loses the point. The rule is here:

"Case 2: A ball in play hits another ball which is lying in the correct court.
What is the correct decision?
Decision: Play continues. However, if it is not clear that the actual ball in
play has been returned, a let should be called."

For instance, if the ball being served is a wilson 3, but the ball that was returned is a Penn 1, then it is clear he returned the wrong ball, and he loses the point in that weird case.

Well, not exactly, because in your scenario (two different kinds of balls), assuming we are playing with two different brand/number of balls, both players would have to know which ball had been served first (the fault). In other words, it is not clear, so a let is played. The only way I see your scenario is if a ball rolls on to the court from an adjacent court in the middle of a point, and my shot hits that ball. In which case, we should have called a let to begin with.

But that wasn't my original question:

Originally Posted by McLovin

Your 1st serve was a fault, but the opponent did not clear the ball from the court and it is sitting inside the lines of play.